Merge latest changes from http://www.netlib.org/fp/dtoa.c into dtoa.cc

base/third_party/dmg_fp/dtoa.cc

Index: base/third_party/dmg_fp/dtoa.cc
diff --git a/base/third_party/dmg_fp/dtoa.cc b/base/third_party/dmg_fp/dtoa.cc
index ba49857514bdec0d20afe22fb41c9ba3585db374..6ab2aefb0bc86e9009d637483f31973ea62ee00b 100644
--- a/base/third_party/dmg_fp/dtoa.cc
+++ b/base/third_party/dmg_fp/dtoa.cc
@@ -103,7 +103,12 @@
  * #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n)
  *	if memory is available and otherwise does something you deem
  *	appropriate.  If MALLOC is undefined, malloc will be invoked
- *	directly -- and assumed always to succeed.
+ *	directly -- and assumed always to succeed.  Similarly, if you
+ *	want something other than the system's free() to be called to
+ *	recycle memory acquired from MALLOC, #define FREE to be the
+ *	name of the alternate routine.  (FREE or free is only called in
+ *	pathological cases, e.g., in a dtoa call after a dtoa return in
+ *	mode 3 with thousands of digits requested.)
  * #define Omit_Private_Memory to omit logic (added Jan. 1998) for making
  *	memory allocations from a private pool of memory when possible.
  *	When used, the private pool is PRIVATE_MEM bytes long:  2304 bytes,
@@ -147,11 +152,6 @@
  *	floating-point numbers and flushes underflows to zero rather
  *	than implementing gradual underflow, then you must also #define
  *	Sudden_Underflow.
- * #define YES_ALIAS to permit aliasing certain double values with
- *	arrays of ULongs.  This leads to slightly better code with
- *	some compilers and was always used prior to 19990916, but it
- *	is not strictly legal and can cause trouble with aggressively
- *	optimizing compilers (e.g., gcc 2.95.1 under -O2).
  * #define USE_LOCALE to use the current locale's decimal_point value.
  * #define SET_INEXACT if IEEE arithmetic is being used and extra
  *	computation should be done to set the inexact flag when the
@@ -169,13 +169,18 @@
  *	inexact or when it is a numeric value rounded to +-infinity).
  * #define NO_ERRNO if strtod should not assign errno = ERANGE when
  *	the result overflows to +-Infinity or underflows to 0.
+ * #define NO_HEX_FP to omit recognition of hexadecimal floating-point
+ *	values by strtod.
+ * #define NO_STRTOD_BIGCOMP (on IEEE-arithmetic systems only for now)
+ *	to disable logic for "fast" testing of very long input strings
+ *	to strtod.  This testing proceeds by initially truncating the
+ *	input string, then if necessary comparing the whole string with
+ *	a decimal expansion to decide close cases. This logic is only
+ *	used for input more than STRTOD_DIGLIM digits long (default 40).
  */
 
 #define IEEE_8087
-#if defined(__GNUC__)
-// Make gcc 4.3+ warnings about parentheses non-fatal warnings.
-#pragma GCC diagnostic warning "-Wparentheses"
-#endif
+#define NO_HEX_FP
 
 #ifndef Long
 #define Long long
@@ -196,6 +201,12 @@ typedef unsigned Long ULong;
 #include "locale.h"
 #endif
 
+#ifdef Honor_FLT_ROUNDS
+#ifndef Trust_FLT_ROUNDS
+#include <fenv.h>
+#endif
+#endif
+
 #ifdef MALLOC
 #ifdef KR_headers
 extern char *MALLOC();
@@ -230,6 +241,7 @@ static double private_mem[PRIVATE_mem], *pmem_next = private_mem;
 #endif
 #else
 #undef INFNAN_CHECK
+#define NO_STRTOD_BIGCOMP
 #endif
 
 #include "errno.h"
@@ -287,24 +299,23 @@ Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined.
 
 typedef union { double d; ULong L[2]; } U;
 
-#ifdef YES_ALIAS
-#define dval(x) x
 #ifdef IEEE_8087
-#define word0(x) ((ULong *)&x)[1]
-#define word1(x) ((ULong *)&x)[0]
+#define word0(x) (x)->L[1]
+#define word1(x) (x)->L[0]
 #else
-#define word0(x) ((ULong *)&x)[0]
-#define word1(x) ((ULong *)&x)[1]
+#define word0(x) (x)->L[0]
+#define word1(x) (x)->L[1]
 #endif
-#else
-#ifdef IEEE_8087
-#define word0(x) ((U*)&x)->L[1]
-#define word1(x) ((U*)&x)->L[0]
-#else
-#define word0(x) ((U*)&x)->L[0]
-#define word1(x) ((U*)&x)->L[1]
+#define dval(x) (x)->d
+
+#ifndef STRTOD_DIGLIM
+#define STRTOD_DIGLIM 40
 #endif
-#define dval(x) ((U*)&x)->d
+
+#ifdef DIGLIM_DEBUG
+extern int strtod_diglim;
+#else
+#define strtod_diglim STRTOD_DIGLIM
 #endif
 
 /* The following definition of Storeinc is appropriate for MIPS processors.
@@ -332,7 +343,9 @@ typedef union { double d; ULong L[2]; } U;
 #define Exp_msk11   0x100000
 #define Exp_mask  0x7ff00000
 #define P 53
+#define Nbits 53
 #define Bias 1023
+#define Emax 1023
 #define Emin (-1022)
 #define Exp_1  0x3ff00000
 #define Exp_11 0x3ff00000
@@ -387,7 +400,10 @@ typedef union { double d; ULong L[2]; } U;
 #define Exp_msk11  0x1000000
 #define Exp_mask  0x7f000000
 #define P 14
+#define Nbits 56
 #define Bias 65
+#define Emax 248
+#define Emin (-260)
 #define Exp_1  0x41000000
 #define Exp_11 0x41000000
 #define Ebits 8	/* exponent has 7 bits, but 8 is the right value in b2d */
@@ -413,7 +429,10 @@ typedef union { double d; ULong L[2]; } U;
 #define Exp_msk11   0x800000
 #define Exp_mask  0x7f80
 #define P 56
+#define Nbits 56
 #define Bias 129
+#define Emax 126
+#define Emin (-129)
 #define Exp_1  0x40800000
 #define Exp_11 0x4080
 #define Ebits 8
@@ -457,6 +476,10 @@ extern double rnd_prod(double, double), rnd_quot(double, double);
 #define Pack_32
 #endif
 
+typedef struct BCinfo BCinfo;
+ struct
+BCinfo { int dp0, dp1, dplen, dsign, e0, inexact, nd, nd0, rounding, scale, uflchk; };
+
 #ifdef KR_headers
 #define FFFFFFFF ((((unsigned long)0xffff)<<16)|(unsigned long)0xffff)
 #else
@@ -487,7 +510,7 @@ extern double rnd_prod(double, double), rnd_quot(double, double);
 #define FREE_DTOA_LOCK(n)	/*nothing*/
 #endif
 
-#define Kmax 15
+#define Kmax 7
 
 double strtod(const char *s00, char **se);
 char *dtoa(double d, int mode, int ndigits,
@@ -519,9 +542,10 @@ Balloc
 #endif
 
 	ACQUIRE_DTOA_LOCK(0);
-	if ((rv = freelist[k])) {
+	/* The k > Kmax case does not need ACQUIRE_DTOA_LOCK(0), */
+	/* but this case seems very unlikely. */
+	if (k <= Kmax && (rv = freelist[k]))
 		freelist[k] = rv->next;
-		}
 	else {
 		x = 1 << k;
 #ifdef Omit_Private_Memory
@@ -529,7 +553,7 @@ Balloc
 #else
 		len = (sizeof(Bigint) + (x-1)*sizeof(ULong) + sizeof(double) - 1)
 			/sizeof(double);
-		if (pmem_next - private_mem + len <= PRIVATE_mem) {
+		if (k <= Kmax && pmem_next - private_mem + len <= PRIVATE_mem) {
 			rv = (Bigint*)pmem_next;
 			pmem_next += len;
 			}
@@ -553,10 +577,18 @@ Bfree
 #endif
 {
 	if (v) {
-		ACQUIRE_DTOA_LOCK(0);
-		v->next = freelist[v->k];
-		freelist[v->k] = v;
-		FREE_DTOA_LOCK(0);
+		if (v->k > Kmax)
+#ifdef FREE
+			FREE((void*)v);
+#else
+			free((void*)v);
+#endif
+		else {
+			ACQUIRE_DTOA_LOCK(0);
+			v->next = freelist[v->k];
+			freelist[v->k] = v;
+			FREE_DTOA_LOCK(0);
+			}
 		}
 	}
 
@@ -623,9 +655,9 @@ multadd
  static Bigint *
 s2b
 #ifdef KR_headers
-	(s, nd0, nd, y9) CONST char *s; int nd0, nd; ULong y9;
+	(s, nd0, nd, y9, dplen) CONST char *s; int nd0, nd, dplen; ULong y9;
 #else
-	(CONST char *s, int nd0, int nd, ULong y9)
+	(CONST char *s, int nd0, int nd, ULong y9, int dplen)
 #endif
 {
 	Bigint *b;
@@ -649,10 +681,10 @@ s2b
 		s += 9;
 		do b = multadd(b, 10, *s++ - '0');
 			while(++i < nd0);
-		s++;
+		s += dplen;
 		}
 	else
-		s += 10;
+		s += dplen + 9;
 	for(; i < nd; i++)
 		b = multadd(b, 10, *s++ - '0');
 	return b;
@@ -661,12 +693,12 @@ s2b
  static int
 hi0bits
 #ifdef KR_headers
-	(x) register ULong x;
+	(x) ULong x;
 #else
-	(register ULong x)
+	(ULong x)
 #endif
 {
-	register int k = 0;
+	int k = 0;
 
 	if (!(x & 0xffff0000)) {
 		k = 16;
@@ -700,8 +732,8 @@ lo0bits
 	(ULong *y)
 #endif
 {
-	register int k;
-	register ULong x = *y;
+	int k;
+	ULong x = *y;
 
 	if (x & 7) {
 		if (x & 1)
@@ -1116,13 +1148,13 @@ diff
  static double
 ulp
 #ifdef KR_headers
-	(x) double x;
+	(x) U *x;
 #else
-	(double x)
+	(U *x)
 #endif
 {
-	register Long L;
-	double a;
+	Long L;
+	U u;
 
 	L = (word0(x) & Exp_mask) - (P-1)*Exp_msk1;
 #ifndef Avoid_Underflow
@@ -1133,26 +1165,26 @@ ulp
 #ifdef IBM
 		L |= Exp_msk1 >> 4;
 #endif
-		word0(a) = L;
-		word1(a) = 0;
+		word0(&u) = L;
+		word1(&u) = 0;
 #ifndef Avoid_Underflow
 #ifndef Sudden_Underflow
 		}
 	else {
 		L = -L >> Exp_shift;
 		if (L < Exp_shift) {
-			word0(a) = 0x80000 >> L;
-			word1(a) = 0;
+			word0(&u) = 0x80000 >> L;
+			word1(&u) = 0;
 			}
 		else {
-			word0(a) = 0;
+			word0(&u) = 0;
 			L -= Exp_shift;
-			word1(a) = L >= 31 ? 1 : 1 << 31 - L;
+			word1(&u) = L >= 31 ? 1 : 1 << 31 - L;
 			}
 		}
 #endif
 #endif
-	return dval(a);
+	return dval(&u);
 	}
 
  static double
@@ -1165,12 +1197,12 @@ b2d
 {
 	ULong *xa, *xa0, w, y, z;
 	int k;
-	double d;
+	U d;
 #ifdef VAX
 	ULong d0, d1;
 #else
-#define d0 word0(d)
-#define d1 word1(d)
+#define d0 word0(&d)
+#define d1 word1(&d)
 #endif
 
 	xa0 = a->x;
@@ -1183,16 +1215,16 @@ b2d
 	*e = 32 - k;
 #ifdef Pack_32
 	if (k < Ebits) {
-		d0 = Exp_1 | y >> Ebits - k;
+		d0 = Exp_1 | y >> (Ebits - k);
 		w = xa > xa0 ? *--xa : 0;
-		d1 = y << (32-Ebits) + k | w >> Ebits - k;
+		d1 = y << ((32-Ebits) + k) | w >> (Ebits - k);
 		goto ret_d;
 		}
 	z = xa > xa0 ? *--xa : 0;
 	if (k -= Ebits) {
-		d0 = Exp_1 | y << k | z >> 32 - k;
+		d0 = Exp_1 | y << k | z >> (32 - k);
 		y = xa > xa0 ? *--xa : 0;
-		d1 = z << k | y >> 32 - k;
+		d1 = z << k | y >> (32 - k);
 		}
 	else {
 		d0 = Exp_1 | y;
@@ -1216,21 +1248,21 @@ b2d
 #endif
  ret_d:
 #ifdef VAX
-	word0(d) = d0 >> 16 | d0 << 16;
-	word1(d) = d1 >> 16 | d1 << 16;
+	word0(&d) = d0 >> 16 | d0 << 16;
+	word1(&d) = d1 >> 16 | d1 << 16;
 #else
 #undef d0
 #undef d1
 #endif
-	return dval(d);
+	return dval(&d);
 	}
 
  static Bigint *
 d2b
 #ifdef KR_headers
-	(d, e, bits) double d; int *e, *bits;
+	(d, e, bits) U *d; int *e, *bits;
 #else
-	(double d, int *e, int *bits)
+	(U *d, int *e, int *bits)
 #endif
 {
 	Bigint *b;
@@ -1269,7 +1301,7 @@ d2b
 #ifdef Pack_32
 	if ((y = d1)) {
 		if ((k = lo0bits(&y))) {
-			x[0] = y | z << 32 - k;
+			x[0] = y | z << (32 - k);
 			z >>= k;
 			}
 		else
@@ -1280,10 +1312,6 @@ d2b
 		    b->wds = (x[1] = z) ? 2 : 1;
 		}
 	else {
-#ifdef DEBUG
-		if (!z)
-			Bug("Zero passed to d2b");
-#endif
 		k = lo0bits(&z);
 		x[0] = z;
 #ifndef Sudden_Underflow
@@ -1371,11 +1399,11 @@ ratio
 	(Bigint *a, Bigint *b)
 #endif
 {
-	double da, db;
+	U da, db;
 	int k, ka, kb;
 
-	dval(da) = b2d(a, &ka);
-	dval(db) = b2d(b, &kb);
+	dval(&da) = b2d(a, &ka);
+	dval(&db) = b2d(b, &kb);
 #ifdef Pack_32
 	k = ka - kb + 32*(a->wds - b->wds);
 #else
@@ -1383,25 +1411,25 @@ ratio
 #endif
 #ifdef IBM
 	if (k > 0) {
-		word0(da) += (k >> 2)*Exp_msk1;
+		word0(&da) += (k >> 2)*Exp_msk1;
 		if (k &= 3)
-			dval(da) *= 1 << k;
+			dval(&da) *= 1 << k;
 		}
 	else {
 		k = -k;
-		word0(db) += (k >> 2)*Exp_msk1;
+		word0(&db) += (k >> 2)*Exp_msk1;
 		if (k &= 3)
-			dval(db) *= 1 << k;
+			dval(&db) *= 1 << k;
 		}
 #else
 	if (k > 0)
-		word0(da) += k*Exp_msk1;
+		word0(&da) += k*Exp_msk1;
 	else {
 		k = -k;
-		word0(db) += k*Exp_msk1;
+		word0(&db) += k*Exp_msk1;
 		}
 #endif
-	return dval(da) / dval(db);
+	return dval(&da) / dval(&db);
 	}
 
  static CONST double
@@ -1441,6 +1469,48 @@ static CONST double tinytens[] = { 1e-16, 1e-32 };
 #endif
 #endif
 
+#undef Need_Hexdig
+#ifdef INFNAN_CHECK
+#ifndef No_Hex_NaN
+#define Need_Hexdig
+#endif
+#endif
+
+#ifndef Need_Hexdig
+#ifndef NO_HEX_FP
+#define Need_Hexdig
+#endif
+#endif
+
+#ifdef Need_Hexdig /*{*/
+static unsigned char hexdig[256];
+
+ static void
+#ifdef KR_headers
+htinit(h, s, inc) unsigned char *h; unsigned char *s; int inc;
+#else
+htinit(unsigned char *h, unsigned char *s, int inc)
+#endif
+{
+	int i, j;
+	for(i = 0; (j = s[i]) !=0; i++)
+		h[j] = i + inc;
+	}
+
+ static void
+#ifdef KR_headers
+hexdig_init()
+#else
+hexdig_init(void)
+#endif
+{
+#define USC (unsigned char *)
+	htinit(hexdig, USC "0123456789", 0x10);
+	htinit(hexdig, USC "abcdef", 0x10 + 10);
+	htinit(hexdig, USC "ABCDEF", 0x10 + 10);
+	}
+#endif /* } Need_Hexdig */
+
 #ifdef INFNAN_CHECK
 
 #ifndef NAN_WORD0
@@ -1476,15 +1546,17 @@ match
  static void
 hexnan
 #ifdef KR_headers
-	(rvp, sp) double *rvp; CONST char **sp;
+	(rvp, sp) U *rvp; CONST char **sp;
 #else
-	(double *rvp, CONST char **sp)
+	(U *rvp, CONST char **sp)
 #endif
 {
 	ULong c, x[2];
 	CONST char *s;
-	int havedig, udx0, xshift;
+	int c1, havedig, udx0, xshift;
 
+	if (!hexdig['0'])
+		hexdig_init();
 	x[0] = x[1] = 0;
 	havedig = xshift = 0;
 	udx0 = 1;
@@ -1495,12 +1567,8 @@ hexnan
 	if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X'))
 		s += 2;
 	while((c = *(CONST unsigned char*)++s)) {
-		if (c >= '0' && c <= '9')
-			c -= '0';
-		else if (c >= 'a' && c <= 'f')
-			c += 10 - 'a';
-		else if (c >= 'A' && c <= 'F')
-			c += 10 - 'A';
+		if ((c1 = hexdig[c]))
+			c  = c1 & 0xf;
 		else if (c <= ' ') {
 			if (udx0 && havedig) {
 				udx0 = 0;
@@ -1537,13 +1605,818 @@ hexnan
 		x[1] = (x[1] << 4) | c;
 		}
 	if ((x[0] &= 0xfffff) || x[1]) {
-		word0(*rvp) = Exp_mask | x[0];
-		word1(*rvp) = x[1];
+		word0(rvp) = Exp_mask | x[0];
+		word1(rvp) = x[1];
 		}
 	}
 #endif /*No_Hex_NaN*/
 #endif /* INFNAN_CHECK */
 
+#ifdef Pack_32
+#define ULbits 32
+#define kshift 5
+#define kmask 31
+#else
+#define ULbits 16
+#define kshift 4
+#define kmask 15
+#endif
+#ifndef NO_HEX_FP /*{*/
+
+ static void
+#ifdef KR_headers
+rshift(b, k) Bigint *b; int k;
+#else
+rshift(Bigint *b, int k)
+#endif
+{
+	ULong *x, *x1, *xe, y;
+	int n;
+
+	x = x1 = b->x;
+	n = k >> kshift;
+	if (n < b->wds) {
+		xe = x + b->wds;
+		x += n;
+		if (k &= kmask) {
+			n = 32 - k;
+			y = *x++ >> k;
+			while(x < xe) {
+				*x1++ = (y | (*x << n)) & 0xffffffff;
+				y = *x++ >> k;
+				}
+			if ((*x1 = y) !=0)
+				x1++;
+			}
+		else
+			while(x < xe)
+				*x1++ = *x++;
+		}
+	if ((b->wds = x1 - b->x) == 0)
+		b->x[0] = 0;
+	}
+
+ static ULong
+#ifdef KR_headers
+any_on(b, k) Bigint *b; int k;
+#else
+any_on(Bigint *b, int k)
+#endif
+{
+	int n, nwds;
+	ULong *x, *x0, x1, x2;
+
+	x = b->x;
+	nwds = b->wds;
+	n = k >> kshift;
+	if (n > nwds)
+		n = nwds;
+	else if (n < nwds && (k &= kmask)) {
+		x1 = x2 = x[n];
+		x1 >>= k;
+		x1 <<= k;
+		if (x1 != x2)
+			return 1;
+		}
+	x0 = x;
+	x += n;
+	while(x > x0)
+		if (*--x)
+			return 1;
+	return 0;
+	}
+
+enum {	/* rounding values: same as FLT_ROUNDS */
+	Round_zero = 0,
+	Round_near = 1,
+	Round_up = 2,
+	Round_down = 3
+	};
+
+ static Bigint *
+#ifdef KR_headers
+increment(b) Bigint *b;
+#else
+increment(Bigint *b)
+#endif
+{
+	ULong *x, *xe;
+	Bigint *b1;
+
+	x = b->x;
+	xe = x + b->wds;
+	do {
+		if (*x < (ULong)0xffffffffL) {
+			++*x;
+			return b;
+			}
+		*x++ = 0;
+		} while(x < xe);
+	{
+		if (b->wds >= b->maxwds) {
+			b1 = Balloc(b->k+1);
+			Bcopy(b1,b);
+			Bfree(b);
+			b = b1;
+			}
+		b->x[b->wds++] = 1;
+		}
+	return b;
+	}
+
+ void
+#ifdef KR_headers
+gethex(sp, rvp, rounding, sign)
+	CONST char **sp; U *rvp; int rounding, sign;
+#else
+gethex( CONST char **sp, U *rvp, int rounding, int sign)
+#endif
+{
+	Bigint *b;
+	CONST unsigned char *decpt, *s0, *s, *s1;
+	Long e, e1;
+	ULong L, lostbits, *x;
+	int big, denorm, esign, havedig, k, n, nbits, up, zret;
+#ifdef IBM
+	int j;
+#endif
+	enum {
+#ifdef IEEE_Arith /*{{*/
+		emax = 0x7fe - Bias - P + 1,
+		emin = Emin - P + 1
+#else /*}{*/
+		emin = Emin - P,
+#ifdef VAX
+		emax = 0x7ff - Bias - P + 1
+#endif
+#ifdef IBM
+		emax = 0x7f - Bias - P
+#endif
+#endif /*}}*/
+		};
+#ifdef USE_LOCALE
+	int i;
+#ifdef NO_LOCALE_CACHE
+	const unsigned char *decimalpoint = (unsigned char*)
+		localeconv()->decimal_point;
+#else
+	const unsigned char *decimalpoint;
+	static unsigned char *decimalpoint_cache;
+	if (!(s0 = decimalpoint_cache)) {
+		s0 = (unsigned char*)localeconv()->decimal_point;
+		if ((decimalpoint_cache = (unsigned char*)
+				MALLOC(strlen((CONST char*)s0) + 1))) {
+			strcpy((char*)decimalpoint_cache, (CONST char*)s0);
+			s0 = decimalpoint_cache;
+			}
+		}
+	decimalpoint = s0;
+#endif
+#endif
+
+	if (!hexdig['0'])
+		hexdig_init();
+	havedig = 0;
+	s0 = *(CONST unsigned char **)sp + 2;
+	while(s0[havedig] == '0')
+		havedig++;
+	s0 += havedig;
+	s = s0;
+	decpt = 0;
+	zret = 0;
+	e = 0;
+	if (hexdig[*s])
+		havedig++;
+	else {
+		zret = 1;
+#ifdef USE_LOCALE
+		for(i = 0; decimalpoint[i]; ++i) {
+			if (s[i] != decimalpoint[i])
+				goto pcheck;
+			}
+		decpt = s += i;
+#else
+		if (*s != '.')
+			goto pcheck;
+		decpt = ++s;
+#endif
+		if (!hexdig[*s])
+			goto pcheck;
+		while(*s == '0')
+			s++;
+		if (hexdig[*s])
+			zret = 0;
+		havedig = 1;
+		s0 = s;
+		}
+	while(hexdig[*s])
+		s++;
+#ifdef USE_LOCALE
+	if (*s == *decimalpoint && !decpt) {
+		for(i = 1; decimalpoint[i]; ++i) {
+			if (s[i] != decimalpoint[i])
+				goto pcheck;
+			}
+		decpt = s += i;
+#else
+	if (*s == '.' && !decpt) {
+		decpt = ++s;
+#endif
+		while(hexdig[*s])
+			s++;
+		}/*}*/
+	if (decpt)
+		e = -(((Long)(s-decpt)) << 2);
+ pcheck:
+	s1 = s;
+	big = esign = 0;
+	switch(*s) {
+	  case 'p':
+	  case 'P':
+		switch(*++s) {
+		  case '-':
+			esign = 1;
+			/* no break */
+		  case '+':
+			s++;
+		  }
+		if ((n = hexdig[*s]) == 0 || n > 0x19) {
+			s = s1;
+			break;
+			}
+		e1 = n - 0x10;
+		while((n = hexdig[*++s]) !=0 && n <= 0x19) {
+			if (e1 & 0xf8000000)
+				big = 1;
+			e1 = 10*e1 + n - 0x10;
+			}
+		if (esign)
+			e1 = -e1;
+		e += e1;
+	  }
+	*sp = (char*)s;
+	if (!havedig)
+		*sp = (char*)s0 - 1;
+	if (zret)
+		goto retz1;
+	if (big) {
+		if (esign) {
+#ifdef IEEE_Arith
+			switch(rounding) {
+			  case Round_up:
+				if (sign)
+					break;
+				goto ret_tiny;
+			  case Round_down:
+				if (!sign)
+					break;
+				goto ret_tiny;
+			  }
+#endif
+			goto retz;
+#ifdef IEEE_Arith
+ ret_tiny:
+#ifndef NO_ERRNO
+			errno = ERANGE;
+#endif
+			word0(rvp) = 0;
+			word1(rvp) = 1;
+			return;
+#endif /* IEEE_Arith */
+			}
+		switch(rounding) {
+		  case Round_near:
+			goto ovfl1;
+		  case Round_up:
+			if (!sign)
+				goto ovfl1;
+			goto ret_big;
+		  case Round_down:
+			if (sign)
+				goto ovfl1;
+			goto ret_big;
+		  }
+ ret_big:
+		word0(rvp) = Big0;
+		word1(rvp) = Big1;
+		return;
+		}
+	n = s1 - s0 - 1;
+	for(k = 0; n > (1 << (kshift-2)) - 1; n >>= 1)
+		k++;
+	b = Balloc(k);
+	x = b->x;
+	n = 0;
+	L = 0;
+#ifdef USE_LOCALE
+	for(i = 0; decimalpoint[i+1]; ++i);
+#endif
+	while(s1 > s0) {
+#ifdef USE_LOCALE
+		if (*--s1 == decimalpoint[i]) {
+			s1 -= i;
+			continue;
+			}
+#else
+		if (*--s1 == '.')
+			continue;
+#endif
+		if (n == ULbits) {
+			*x++ = L;
+			L = 0;
+			n = 0;
+			}
+		L |= (hexdig[*s1] & 0x0f) << n;
+		n += 4;
+		}
+	*x++ = L;
+	b->wds = n = x - b->x;
+	n = ULbits*n - hi0bits(L);
+	nbits = Nbits;
+	lostbits = 0;
+	x = b->x;
+	if (n > nbits) {
+		n -= nbits;
+		if (any_on(b,n)) {
+			lostbits = 1;
+			k = n - 1;
+			if (x[k>>kshift] & 1 << (k & kmask)) {
+				lostbits = 2;
+				if (k > 0 && any_on(b,k))
+					lostbits = 3;
+				}
+			}
+		rshift(b, n);
+		e += n;
+		}
+	else if (n < nbits) {
+		n = nbits - n;
+		b = lshift(b, n);
+		e -= n;
+		x = b->x;
+		}
+	if (e > Emax) {
+ ovfl:
+		Bfree(b);
+ ovfl1:
+#ifndef NO_ERRNO
+		errno = ERANGE;
+#endif
+		word0(rvp) = Exp_mask;
+		word1(rvp) = 0;
+		return;
+		}
+	denorm = 0;
+	if (e < emin) {
+		denorm = 1;
+		n = emin - e;
+		if (n >= nbits) {
+#ifdef IEEE_Arith /*{*/
+			switch (rounding) {
+			  case Round_near:
+				if (n == nbits && (n < 2 || any_on(b,n-1)))
+					goto ret_tiny;
+				break;
+			  case Round_up:
+				if (!sign)
+					goto ret_tiny;
+				break;
+			  case Round_down:
+				if (sign)
+					goto ret_tiny;
+			  }
+#endif /* } IEEE_Arith */
+			Bfree(b);
+ retz:
+#ifndef NO_ERRNO
+			errno = ERANGE;
+#endif
+ retz1:
+			rvp->d = 0.;
+			return;
+			}
+		k = n - 1;
+		if (lostbits)
+			lostbits = 1;
+		else if (k > 0)
+			lostbits = any_on(b,k);
+		if (x[k>>kshift] & 1 << (k & kmask))
+			lostbits |= 2;
+		nbits -= n;
+		rshift(b,n);
+		e = emin;
+		}
+	if (lostbits) {
+		up = 0;
+		switch(rounding) {
+		  case Round_zero:
+			break;
+		  case Round_near:
+			if (lostbits & 2
+			 && (lostbits & 1) | (x[0] & 1))
+				up = 1;
+			break;
+		  case Round_up:
+			up = 1 - sign;
+			break;
+		  case Round_down:
+			up = sign;
+		  }
+		if (up) {
+			k = b->wds;
+			b = increment(b);
+			x = b->x;
+			if (denorm) {
+#if 0
+				if (nbits == Nbits - 1
+				 && x[nbits >> kshift] & 1 << (nbits & kmask))
+					denorm = 0; /* not currently used */
+#endif
+				}
+			else if (b->wds > k
+			 || ((n = nbits & kmask) !=0
+			     && hi0bits(x[k-1]) < 32-n)) {
+				rshift(b,1);
+				if (++e > Emax)
+					goto ovfl;
+				}
+			}
+		}
+#ifdef IEEE_Arith
+	if (denorm)
+		word0(rvp) = b->wds > 1 ? b->x[1] & ~0x100000 : 0;
+	else
+		word0(rvp) = (b->x[1] & ~0x100000) | ((e + 0x3ff + 52) << 20);
+	word1(rvp) = b->x[0];
+#endif
+#ifdef IBM
+	if ((j = e & 3)) {
+		k = b->x[0] & ((1 << j) - 1);
+		rshift(b,j);
+		if (k) {
+			switch(rounding) {
+			  case Round_up:
+				if (!sign)
+					increment(b);
+				break;
+			  case Round_down:
+				if (sign)
+					increment(b);
+				break;
+			  case Round_near:
+				j = 1 << (j-1);
+				if (k & j && ((k & (j-1)) | lostbits))
+					increment(b);
+			  }
+			}
+		}
+	e >>= 2;
+	word0(rvp) = b->x[1] | ((e + 65 + 13) << 24);
+	word1(rvp) = b->x[0];
+#endif
+#ifdef VAX
+	/* The next two lines ignore swap of low- and high-order 2 bytes. */
+	/* word0(rvp) = (b->x[1] & ~0x800000) | ((e + 129 + 55) << 23); */
+	/* word1(rvp) = b->x[0]; */
+	word0(rvp) = ((b->x[1] & ~0x800000) >> 16) | ((e + 129 + 55) << 7) | (b->x[1] << 16);
+	word1(rvp) = (b->x[0] >> 16) | (b->x[0] << 16);
+#endif
+	Bfree(b);
+	}
+#endif /*}!NO_HEX_FP*/
+
+ static int
+#ifdef KR_headers
+dshift(b, p2) Bigint *b; int p2;
+#else
+dshift(Bigint *b, int p2)
+#endif
+{
+	int rv = hi0bits(b->x[b->wds-1]) - 4;
+	if (p2 > 0)
+		rv -= p2;
+	return rv & kmask;
+	}
+
+ static int
+quorem
+#ifdef KR_headers
+	(b, S) Bigint *b, *S;
+#else
+	(Bigint *b, Bigint *S)
+#endif
+{
+	int n;
+	ULong *bx, *bxe, q, *sx, *sxe;
+#ifdef ULLong
+	ULLong borrow, carry, y, ys;
+#else
+	ULong borrow, carry, y, ys;
+#ifdef Pack_32
+	ULong si, z, zs;
+#endif
+#endif
+
+	n = S->wds;
+#ifdef DEBUG
+	/*debug*/ if (b->wds > n)
+	/*debug*/	Bug("oversize b in quorem");
+#endif
+	if (b->wds < n)
+		return 0;
+	sx = S->x;
+	sxe = sx + --n;
+	bx = b->x;
+	bxe = bx + n;
+	q = *bxe / (*sxe + 1);	/* ensure q <= true quotient */
+#ifdef DEBUG
+	/*debug*/ if (q > 9)
+	/*debug*/	Bug("oversized quotient in quorem");
+#endif
+	if (q) {
+		borrow = 0;
+		carry = 0;
+		do {
+#ifdef ULLong
+			ys = *sx++ * (ULLong)q + carry;
+			carry = ys >> 32;
+			y = *bx - (ys & FFFFFFFF) - borrow;
+			borrow = y >> 32 & (ULong)1;
+			*bx++ = y & FFFFFFFF;
+#else
+#ifdef Pack_32
+			si = *sx++;
+			ys = (si & 0xffff) * q + carry;
+			zs = (si >> 16) * q + (ys >> 16);
+			carry = zs >> 16;
+			y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
+			borrow = (y & 0x10000) >> 16;
+			z = (*bx >> 16) - (zs & 0xffff) - borrow;
+			borrow = (z & 0x10000) >> 16;
+			Storeinc(bx, z, y);
+#else
+			ys = *sx++ * q + carry;
+			carry = ys >> 16;
+			y = *bx - (ys & 0xffff) - borrow;
+			borrow = (y & 0x10000) >> 16;
+			*bx++ = y & 0xffff;
+#endif
+#endif
+			}
+			while(sx <= sxe);
+		if (!*bxe) {
+			bx = b->x;
+			while(--bxe > bx && !*bxe)
+				--n;
+			b->wds = n;
+			}
+		}
+	if (cmp(b, S) >= 0) {
+		q++;
+		borrow = 0;
+		carry = 0;
+		bx = b->x;
+		sx = S->x;
+		do {
+#ifdef ULLong
+			ys = *sx++ + carry;
+			carry = ys >> 32;
+			y = *bx - (ys & FFFFFFFF) - borrow;
+			borrow = y >> 32 & (ULong)1;
+			*bx++ = y & FFFFFFFF;
+#else
+#ifdef Pack_32
+			si = *sx++;
+			ys = (si & 0xffff) + carry;
+			zs = (si >> 16) + (ys >> 16);
+			carry = zs >> 16;
+			y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
+			borrow = (y & 0x10000) >> 16;
+			z = (*bx >> 16) - (zs & 0xffff) - borrow;
+			borrow = (z & 0x10000) >> 16;
+			Storeinc(bx, z, y);
+#else
+			ys = *sx++ + carry;
+			carry = ys >> 16;
+			y = *bx - (ys & 0xffff) - borrow;
+			borrow = (y & 0x10000) >> 16;
+			*bx++ = y & 0xffff;
+#endif
+#endif
+			}
+			while(sx <= sxe);
+		bx = b->x;
+		bxe = bx + n;
+		if (!*bxe) {
+			while(--bxe > bx && !*bxe)
+				--n;
+			b->wds = n;
+			}
+		}
+	return q;
+	}
+
+#ifndef NO_STRTOD_BIGCOMP
+
+ static void
+bigcomp
+#ifdef KR_headers
+	(rv, s0, bc)
+	U *rv; CONST char *s0; BCinfo *bc;
+#else
+	(U *rv, CONST char *s0, BCinfo *bc)
+#endif
+{
+	Bigint *b, *d;
+	int b2, bbits, d2, dd, dig, dsign, i, j, nd, nd0, p2, p5, speccase;
+
+	dsign = bc->dsign;
+	nd = bc->nd;
+	nd0 = bc->nd0;
+	p5 = nd + bc->e0 - 1;
+	speccase = 0;
+#ifndef Sudden_Underflow
+	if (rv->d == 0.) {	/* special case: value near underflow-to-zero */
+				/* threshold was rounded to zero */
+		b = i2b(1);
+		p2 = Emin - P + 1;
+		bbits = 1;
+#ifdef Avoid_Underflow
+		word0(rv) = (P+2) << Exp_shift;
+#else
+		word1(rv) = 1;
+#endif
+		i = 0;
+#ifdef Honor_FLT_ROUNDS
+		if (bc->rounding == 1)
+#endif
+			{
+			speccase = 1;
+			--p2;
+			dsign = 0;
+			goto have_i;
+			}
+		}
+	else
+#endif
+		b = d2b(rv, &p2, &bbits);
+#ifdef Avoid_Underflow
+	p2 -= bc->scale;
+#endif
+	/* floor(log2(rv)) == bbits - 1 + p2 */
+	/* Check for denormal case. */
+	i = P - bbits;
+	if (i > (j = P - Emin - 1 + p2)) {
+#ifdef Sudden_Underflow
+		Bfree(b);
+		b = i2b(1);
+		p2 = Emin;
+		i = P - 1;
+#ifdef Avoid_Underflow
+		word0(rv) = (1 + bc->scale) << Exp_shift;
+#else
+		word0(rv) = Exp_msk1;
+#endif
+		word1(rv) = 0;
+#else
+		i = j;
+#endif
+		}
+#ifdef Honor_FLT_ROUNDS
+	if (bc->rounding != 1) {
+		if (i > 0)
+			b = lshift(b, i);
+		if (dsign)
+			b = increment(b);
+		}
+	else
+#endif
+		{
+		b = lshift(b, ++i);
+		b->x[0] |= 1;
+		}
+#ifndef Sudden_Underflow
+ have_i:
+#endif
+	p2 -= p5 + i;
+	d = i2b(1);
+	/* Arrange for convenient computation of quotients:
+	 * shift left if necessary so divisor has 4 leading 0 bits.
+	 */
+	if (p5 > 0)
+		d = pow5mult(d, p5);
+	else if (p5 < 0)
+		b = pow5mult(b, -p5);
+	if (p2 > 0) {
+		b2 = p2;
+		d2 = 0;
+		}
+	else {
+		b2 = 0;
+		d2 = -p2;
+		}
+	i = dshift(d, d2);
+	if ((b2 += i) > 0)
+		b = lshift(b, b2);
+	if ((d2 += i) > 0)
+		d = lshift(d, d2);
+
+	/* Now b/d = exactly half-way between the two floating-point values */
+	/* on either side of the input string.  Compute first digit of b/d. */
+
+	if (!(dig = quorem(b,d))) {
+		b = multadd(b, 10, 0);	/* very unlikely */
+		dig = quorem(b,d);
+		}
+
+	/* Compare b/d with s0 */
+
+	for(i = 0; i < nd0; ) {
+		if ((dd = s0[i++] - '0' - dig))
+			goto ret;
+		if (!b->x[0] && b->wds == 1) {
+			if (i < nd)
+				dd = 1;
+			goto ret;
+			}
+		b = multadd(b, 10, 0);
+		dig = quorem(b,d);
+		}
+	for(j = bc->dp1; i++ < nd;) {
+		if ((dd = s0[j++] - '0' - dig))
+			goto ret;
+		if (!b->x[0] && b->wds == 1) {
+			if (i < nd)
+				dd = 1;
+			goto ret;
+			}
+		b = multadd(b, 10, 0);
+		dig = quorem(b,d);
+		}
+	if (b->x[0] || b->wds > 1)
+		dd = -1;
+ ret:
+	Bfree(b);
+	Bfree(d);
+#ifdef Honor_FLT_ROUNDS
+	if (bc->rounding != 1) {
+		if (dd < 0) {
+			if (bc->rounding == 0) {
+				if (!dsign)
+					goto retlow1;
+				}
+			else if (dsign)
+				goto rethi1;
+			}
+		else if (dd > 0) {
+			if (bc->rounding == 0) {
+				if (dsign)
+					goto rethi1;
+				goto ret1;
+				}
+			if (!dsign)
+				goto rethi1;
+			dval(rv) += 2.*ulp(rv);
+			}
+		else {
+			bc->inexact = 0;
+			if (dsign)
+				goto rethi1;
+			}
+		}
+	else
+#endif
+	if (speccase) {
+		if (dd <= 0)
+			rv->d = 0.;
+		}
+	else if (dd < 0) {
+		if (!dsign)	/* does not happen for round-near */
+retlow1:
+			dval(rv) -= ulp(rv);
+		}
+	else if (dd > 0) {
+		if (dsign) {
+ rethi1:
+			dval(rv) += ulp(rv);
+			}
+		}
+	else {
+		/* Exact half-way case:  apply round-even rule. */
+		if (word1(rv) & 1) {
+			if (dsign)
+				goto rethi1;
+			goto retlow1;
+			}
+		}
+
+#ifdef Honor_FLT_ROUNDS
+ ret1:
+#endif
+	return;
+	}
+#endif /* NO_STRTOD_BIGCOMP */
+
  double
 strtod
 #ifdef KR_headers
@@ -1552,29 +2425,27 @@ strtod
 	(CONST char *s00, char **se)
 #endif
 {
-#ifdef Avoid_Underflow
-	int scale;
-#endif
-	int bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, dsign,
-		 e, e1, esign, i, j, k, nd, nd0, nf, nz, nz0, sign;
+	int bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, e, e1;
+	int esign, i, j, k, nd, nd0, nf, nz, nz0, sign;
 	CONST char *s, *s0, *s1;
-	double aadj, aadj1, adj, rv, rv0;
+	double aadj, aadj1;
 	Long L;
+	U aadj2, adj, rv, rv0;
 	ULong y, z;
+	BCinfo bc;
 	Bigint *bb, *bb1, *bd, *bd0, *bs, *delta;
 #ifdef SET_INEXACT
-	int inexact, oldinexact;
+	int oldinexact;
 #endif
 #ifdef Honor_FLT_ROUNDS /*{*/
-	int Rounding;
 #ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
-	Rounding = Flt_Rounds;
+	bc.rounding = Flt_Rounds;
 #else /*}{*/
-	Rounding = 1;
+	bc.rounding = 1;
 	switch(fegetround()) {
-	  case FE_TOWARDZERO:	Rounding = 0; break;
-	  case FE_UPWARD:	Rounding = 2; break;
-	  case FE_DOWNWARD:	Rounding = 3;
+	  case FE_TOWARDZERO:	bc.rounding = 0; break;
+	  case FE_UPWARD:	bc.rounding = 2; break;
+	  case FE_DOWNWARD:	bc.rounding = 3;
 	  }
 #endif /*}}*/
 #endif /*}*/
@@ -1582,8 +2453,8 @@ strtod
 	CONST char *s2;
 #endif
 
-	sign = nz0 = nz = 0;
-	dval(rv) = 0.;
+	sign = nz0 = nz = bc.dplen = bc.uflchk = 0;
+	dval(&rv) = 0.;
 	for(s = s00;;s++) switch(*s) {
 		case '-':
 			sign = 1;
@@ -1606,6 +2477,18 @@ strtod
 		}
  break2:
 	if (*s == '0') {
+#ifndef NO_HEX_FP /*{*/
+		switch(s[1]) {
+		  case 'x':
+		  case 'X':
+#ifdef Honor_FLT_ROUNDS
+			gethex(&s, &rv, bc.rounding, sign);
+#else
+			gethex(&s, &rv, 1, sign);
+#endif
+			goto ret;
+		  }
+#endif /*}*/
 		nz0 = 1;
 		while(*++s == '0') ;
 		if (!*s)
@@ -1619,6 +2502,7 @@ strtod
 		else if (nd < 16)
 			z = 10*z + c - '0';
 	nd0 = nd;
+	bc.dp0 = bc.dp1 = s - s0;
 #ifdef USE_LOCALE
 	s1 = localeconv()->decimal_point;
 	if (c == *s1) {
@@ -1640,6 +2524,8 @@ strtod
 #endif
 	if (c == '.') {
 		c = *++s;
+		bc.dp1 = s - s0;
+		bc.dplen = bc.dp1 - bc.dp0;
 		if (!nd) {
 			for(; c == '0'; c = *++s)
 				nz++;
@@ -1711,23 +2597,24 @@ strtod
 		if (!nz && !nz0) {
 #ifdef INFNAN_CHECK
 			/* Check for Nan and Infinity */
-			switch(c) {
+			if (!bc.dplen)
+			 switch(c) {
 			  case 'i':
 			  case 'I':
 				if (match(&s,"nf")) {
 					--s;
 					if (!match(&s,"inity"))
 						++s;
-					word0(rv) = 0x7ff00000;
-					word1(rv) = 0;
+					word0(&rv) = 0x7ff00000;
+					word1(&rv) = 0;
 					goto ret;
 					}
 				break;
 			  case 'n':
 			  case 'N':
 				if (match(&s, "an")) {
-					word0(rv) = NAN_WORD0;
-					word1(rv) = NAN_WORD1;
+					word0(&rv) = NAN_WORD0;
+					word1(&rv) = NAN_WORD1;
 #ifndef No_Hex_NaN
 					if (*s == '(') /*)*/
 						hexnan(&rv, &s);
@@ -1742,7 +2629,7 @@ strtod
 			}
 		goto ret;
 		}
-	e1 = e -= nf;
+	bc.e0 = e1 = e -= nf;
 
 	/* Now we have nd0 digits, starting at s0, followed by a
 	 * decimal point, followed by nd-nd0 digits.  The number we're
@@ -1752,13 +2639,13 @@ strtod
 	if (!nd0)
 		nd0 = nd;
 	k = nd < DBL_DIG + 1 ? nd : DBL_DIG + 1;
-	dval(rv) = y;
+	dval(&rv) = y;
 	if (k > 9) {
 #ifdef SET_INEXACT
 		if (k > DBL_DIG)
 			oldinexact = get_inexact();
 #endif
-		dval(rv) = tens[k - 9] * dval(rv) + z;
+		dval(&rv) = tens[k - 9] * dval(&rv) + z;
 		}
 	bd0 = 0;
 	if (nd <= DBL_DIG
@@ -1778,11 +2665,11 @@ strtod
 #ifdef Honor_FLT_ROUNDS
 				/* round correctly FLT_ROUNDS = 2 or 3 */
 				if (sign) {
-					rv = -rv;
+					rv.d = -rv.d;
 					sign = 0;
 					}
 #endif
-				/* rv = */ rounded_product(dval(rv), tens[e]);
+				/* rv = */ rounded_product(dval(&rv), tens[e]);
 				goto ret;
 #endif
 				}
@@ -1794,25 +2681,25 @@ strtod
 #ifdef Honor_FLT_ROUNDS
 				/* round correctly FLT_ROUNDS = 2 or 3 */
 				if (sign) {
-					rv = -rv;
+					rv.d = -rv.d;
 					sign = 0;
 					}
 #endif
 				e -= i;
-				dval(rv) *= tens[i];
+				dval(&rv) *= tens[i];
 #ifdef VAX
 				/* VAX exponent range is so narrow we must
 				 * worry about overflow here...
 				 */
  vax_ovfl_check:
-				word0(rv) -= P*Exp_msk1;
-				/* rv = */ rounded_product(dval(rv), tens[e]);
-				if ((word0(rv) & Exp_mask)
+				word0(&rv) -= P*Exp_msk1;
+				/* rv = */ rounded_product(dval(&rv), tens[e]);
+				if ((word0(&rv) & Exp_mask)
 				 > Exp_msk1*(DBL_MAX_EXP+Bias-1-P))
 					goto ovfl;
-				word0(rv) += P*Exp_msk1;
+				word0(&rv) += P*Exp_msk1;
 #else
-				/* rv = */ rounded_product(dval(rv), tens[e]);
+				/* rv = */ rounded_product(dval(&rv), tens[e]);
 #endif
 				goto ret;
 				}
@@ -1822,11 +2709,11 @@ strtod
 #ifdef Honor_FLT_ROUNDS
 			/* round correctly FLT_ROUNDS = 2 or 3 */
 			if (sign) {
-				rv = -rv;
+				rv.d = -rv.d;
 				sign = 0;
 				}
 #endif
-			/* rv = */ rounded_quotient(dval(rv), tens[-e]);
+			/* rv = */ rounded_quotient(dval(&rv), tens[-e]);
 			goto ret;
 			}
 #endif
@@ -1835,20 +2722,20 @@ strtod
 
 #ifdef IEEE_Arith
 #ifdef SET_INEXACT
-	inexact = 1;
+	bc.inexact = 1;
 	if (k <= DBL_DIG)
 		oldinexact = get_inexact();
 #endif
 #ifdef Avoid_Underflow
-	scale = 0;
+	bc.scale = 0;
 #endif
 #ifdef Honor_FLT_ROUNDS
-	if (Rounding >= 2) {
+	if (bc.rounding >= 2) {
 		if (sign)
-			Rounding = Rounding == 2 ? 0 : 2;
+			bc.rounding = bc.rounding == 2 ? 0 : 2;
 		else
-			if (Rounding != 2)
-				Rounding = 0;
+			if (bc.rounding != 2)
+				bc.rounding = 0;
 		}
 #endif
 #endif /*IEEE_Arith*/
@@ -1857,7 +2744,7 @@ strtod
 
 	if (e1 > 0) {
 		if ((i = e1 & 15))
-			dval(rv) *= tens[i];
+			dval(&rv) *= tens[i];
 		if (e1 &= ~15) {
 			if (e1 > DBL_MAX_10_EXP) {
  ovfl:
@@ -1867,103 +2754,99 @@ strtod
 				/* Can't trust HUGE_VAL */
 #ifdef IEEE_Arith
 #ifdef Honor_FLT_ROUNDS
-				switch(Rounding) {
+				switch(bc.rounding) {
 				  case 0: /* toward 0 */
 				  case 3: /* toward -infinity */
-					word0(rv) = Big0;
-					word1(rv) = Big1;
+					word0(&rv) = Big0;
+					word1(&rv) = Big1;
 					break;
 				  default:
-					word0(rv) = Exp_mask;
-					word1(rv) = 0;
+					word0(&rv) = Exp_mask;
+					word1(&rv) = 0;
 				  }
 #else /*Honor_FLT_ROUNDS*/
-				word0(rv) = Exp_mask;
-				word1(rv) = 0;
+				word0(&rv) = Exp_mask;
+				word1(&rv) = 0;
 #endif /*Honor_FLT_ROUNDS*/
 #ifdef SET_INEXACT
 				/* set overflow bit */
-				dval(rv0) = 1e300;
-				dval(rv0) *= dval(rv0);
+				dval(&rv0) = 1e300;
+				dval(&rv0) *= dval(&rv0);
 #endif
 #else /*IEEE_Arith*/
-				word0(rv) = Big0;
-				word1(rv) = Big1;
+				word0(&rv) = Big0;
+				word1(&rv) = Big1;
 #endif /*IEEE_Arith*/
-				if (bd0)
-					goto retfree;
 				goto ret;
 				}
 			e1 >>= 4;
 			for(j = 0; e1 > 1; j++, e1 >>= 1)
 				if (e1 & 1)
-					dval(rv) *= bigtens[j];
+					dval(&rv) *= bigtens[j];
 		/* The last multiplication could overflow. */
-			word0(rv) -= P*Exp_msk1;
-			dval(rv) *= bigtens[j];
-			if ((z = word0(rv) & Exp_mask)
+			word0(&rv) -= P*Exp_msk1;
+			dval(&rv) *= bigtens[j];
+			if ((z = word0(&rv) & Exp_mask)
 			 > Exp_msk1*(DBL_MAX_EXP+Bias-P))
 				goto ovfl;
 			if (z > Exp_msk1*(DBL_MAX_EXP+Bias-1-P)) {
 				/* set to largest number */
 				/* (Can't trust DBL_MAX) */
-				word0(rv) = Big0;
-				word1(rv) = Big1;
+				word0(&rv) = Big0;
+				word1(&rv) = Big1;
 				}
 			else
-				word0(rv) += P*Exp_msk1;
+				word0(&rv) += P*Exp_msk1;
 			}
 		}
 	else if (e1 < 0) {
 		e1 = -e1;
 		if ((i = e1 & 15))
-			dval(rv) /= tens[i];
+			dval(&rv) /= tens[i];
 		if (e1 >>= 4) {
 			if (e1 >= 1 << n_bigtens)
 				goto undfl;
 #ifdef Avoid_Underflow
 			if (e1 & Scale_Bit)
-				scale = 2*P;
+				bc.scale = 2*P;
 			for(j = 0; e1 > 0; j++, e1 >>= 1)
 				if (e1 & 1)
-					dval(rv) *= tinytens[j];
-			if (scale && (j = 2*P + 1 - ((word0(rv) & Exp_mask)
+					dval(&rv) *= tinytens[j];
+			if (bc.scale && (j = 2*P + 1 - ((word0(&rv) & Exp_mask)
 						>> Exp_shift)) > 0) {
 				/* scaled rv is denormal; clear j low bits */
 				if (j >= 32) {
-					word1(rv) = 0;
+					word1(&rv) = 0;
 					if (j >= 53)
-					 word0(rv) = (P+2)*Exp_msk1;
+					 word0(&rv) = (P+2)*Exp_msk1;
 					else
-					 word0(rv) &= 0xffffffff << j-32;
+					 word0(&rv) &= 0xffffffff << (j-32);
 					}
 				else
-					word1(rv) &= 0xffffffff << j;
+					word1(&rv) &= 0xffffffff << j;
 				}
 #else
 			for(j = 0; e1 > 1; j++, e1 >>= 1)
 				if (e1 & 1)
-					dval(rv) *= tinytens[j];
+					dval(&rv) *= tinytens[j];
 			/* The last multiplication could underflow. */
-			dval(rv0) = dval(rv);
-			dval(rv) *= tinytens[j];
-			if (!dval(rv)) {
-				dval(rv) = 2.*dval(rv0);
-				dval(rv) *= tinytens[j];
+			dval(&rv0) = dval(&rv);
+			dval(&rv) *= tinytens[j];
+			if (!dval(&rv)) {
+				dval(&rv) = 2.*dval(&rv0);
+				dval(&rv) *= tinytens[j];
 #endif
-				if (!dval(rv)) {
+				if (!dval(&rv)) {
  undfl:
-					dval(rv) = 0.;
+					dval(&rv) = 0.;
 #ifndef NO_ERRNO
 					errno = ERANGE;
 #endif
-					if (bd0)
-						goto retfree;
 					goto ret;
 					}
 #ifndef Avoid_Underflow
-				word0(rv) = Tiny0;
-				word1(rv) = Tiny1;
+				word0(&rv) = Tiny0;
+				word1(&rv) = Tiny1;
 				/* The refinement below will clean
 				 * this approximation up.
 				 */
@@ -1976,12 +2859,44 @@ strtod
 
 	/* Put digits into bd: true value = bd * 10^e */
 
-	bd0 = s2b(s0, nd0, nd, y);
+	bc.nd = nd;
+#ifndef NO_STRTOD_BIGCOMP
+	bc.nd0 = nd0;	/* Only needed if nd > strtod_diglim, but done here */
+			/* to silence an erroneous warning about bc.nd0 */
+			/* possibly not being initialized. */
+	if (nd > strtod_diglim) {
+		/* ASSERT(strtod_diglim >= 18); 18 == one more than the */
+		/* minimum number of decimal digits to distinguish double values */
+		/* in IEEE arithmetic. */
+		i = j = 18;
+		if (i > nd0)
+			j += bc.dplen;
+		for(;;) {
+			if (--j <= bc.dp1 && j >= bc.dp0)
+				j = bc.dp0 - 1;
+			if (s0[j] != '0')
+				break;
+			--i;
+			}
+		e += nd - i;
+		nd = i;
+		if (nd0 > nd)
+			nd0 = nd;
+		if (nd < 9) { /* must recompute y */
+			y = 0;
+			for(i = 0; i < nd0; ++i)
+				y = 10*y + s0[i] - '0';
+			for(j = bc.dp1; i < nd; ++i)
+				y = 10*y + s0[j++] - '0';
+			}
+		}
+#endif
+	bd0 = s2b(s0, nd0, nd, y, bc.dplen);
 
 	for(;;) {
 		bd = Balloc(bd0->k);
 		Bcopy(bd, bd0);
-		bb = d2b(dval(rv), &bbe, &bbbits);	/* rv = bb * 2^bbe */
+		bb = d2b(&rv, &bbe, &bbbits);	/* rv = bb * 2^bbe */
 		bs = i2b(1);
 
 		if (e >= 0) {
@@ -1998,11 +2913,11 @@ strtod
 			bd2 -= bbe;
 		bs2 = bb2;
 #ifdef Honor_FLT_ROUNDS
-		if (Rounding != 1)
+		if (bc.rounding != 1)
 			bs2++;
 #endif
 #ifdef Avoid_Underflow
-		j = bbe - scale;
+		j = bbe - bc.scale;
 		i = j + bbbits - 1;	/* logb(rv) */
 		if (i < Emin)	/* denormal */
 			j += P - Emin;
@@ -2027,7 +2942,7 @@ strtod
 		bb2 += j;
 		bd2 += j;
 #ifdef Avoid_Underflow
-		bd2 += scale;
+		bd2 += bc.scale;
 #endif
 		i = bb2 < bd2 ? bb2 : bd2;
 		if (i > bs2)
@@ -2052,99 +2967,116 @@ strtod
 		if (bs2 > 0)
 			bs = lshift(bs, bs2);
 		delta = diff(bb, bd);
-		dsign = delta->sign;
+		bc.dsign = delta->sign;
 		delta->sign = 0;
 		i = cmp(delta, bs);
+#ifndef NO_STRTOD_BIGCOMP
+		if (bc.nd > nd && i <= 0) {
+			if (bc.dsign)
+				break;	/* Must use bigcomp(). */
 #ifdef Honor_FLT_ROUNDS
-		if (Rounding != 1) {
+			if (bc.rounding != 1) {
+				if (i < 0)
+					break;
+				}
+			else
+#endif
+				{
+				bc.nd = nd;
+				i = -1;	/* Discarded digits make delta smaller. */
+				}
+			}
+#endif
+#ifdef Honor_FLT_ROUNDS
+		if (bc.rounding != 1) {
 			if (i < 0) {
 				/* Error is less than an ulp */
 				if (!delta->x[0] && delta->wds <= 1) {
 					/* exact */
 #ifdef SET_INEXACT
-					inexact = 0;
+					bc.inexact = 0;
 #endif
 					break;
 					}
-				if (Rounding) {
-					if (dsign) {
-						adj = 1.;
+				if (bc.rounding) {
+					if (bc.dsign) {
+						adj.d = 1.;
 						goto apply_adj;
 						}
 					}
-				else if (!dsign) {
-					adj = -1.;
-					if (!word1(rv)
-					 && !(word0(rv) & Frac_mask)) {
-						y = word0(rv) & Exp_mask;
+				else if (!bc.dsign) {
+					adj.d = -1.;
+					if (!word1(&rv)
+					 && !(word0(&rv) & Frac_mask)) {
+						y = word0(&rv) & Exp_mask;
 #ifdef Avoid_Underflow
-						if (!scale || y > 2*P*Exp_msk1)
+						if (!bc.scale || y > 2*P*Exp_msk1)
 #else
 						if (y)
 #endif
 						  {
 						  delta = lshift(delta,Log2P);
 						  if (cmp(delta, bs) <= 0)
-							adj = -0.5;
+							adj.d = -0.5;
 						  }
 						}
  apply_adj:
 #ifdef Avoid_Underflow
-					if (scale && (y = word0(rv) & Exp_mask)
+					if (bc.scale && (y = word0(&rv) & Exp_mask)
 						<= 2*P*Exp_msk1)
-					  word0(adj) += (2*P+1)*Exp_msk1 - y;
+					  word0(&adj) += (2*P+1)*Exp_msk1 - y;
 #else
 #ifdef Sudden_Underflow
-					if ((word0(rv) & Exp_mask) <=
+					if ((word0(&rv) & Exp_mask) <=
 							P*Exp_msk1) {
-						word0(rv) += P*Exp_msk1;
-						dval(rv) += adj*ulp(dval(rv));
-						word0(rv) -= P*Exp_msk1;
+						word0(&rv) += P*Exp_msk1;
+						dval(&rv) += adj.d*ulp(dval(&rv));
+						word0(&rv) -= P*Exp_msk1;
 						}
 					else
 #endif /*Sudden_Underflow*/
 #endif /*Avoid_Underflow*/
-					dval(rv) += adj*ulp(dval(rv));
+					dval(&rv) += adj.d*ulp(&rv);
 					}
 				break;
 				}
-			adj = ratio(delta, bs);
-			if (adj < 1.)
-				adj = 1.;
-			if (adj <= 0x7ffffffe) {
+			adj.d = ratio(delta, bs);
+			if (adj.d < 1.)
+				adj.d = 1.;
+			if (adj.d <= 0x7ffffffe) {
 				/* adj = rounding ? ceil(adj) : floor(adj); */
-				y = adj;
-				if (y != adj) {
-					if (!((Rounding>>1) ^ dsign))
+				y = adj.d;
+				if (y != adj.d) {
+					if (!((bc.rounding>>1) ^ bc.dsign))
 						y++;
-					adj = y;
+					adj.d = y;
 					}
 				}
 #ifdef Avoid_Underflow
-			if (scale && (y = word0(rv) & Exp_mask) <= 2*P*Exp_msk1)
-				word0(adj) += (2*P+1)*Exp_msk1 - y;
+			if (bc.scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
+				word0(&adj) += (2*P+1)*Exp_msk1 - y;
 #else
 #ifdef Sudden_Underflow
-			if ((word0(rv) & Exp_mask) <= P*Exp_msk1) {
-				word0(rv) += P*Exp_msk1;
-				adj *= ulp(dval(rv));
-				if (dsign)
-					dval(rv) += adj;
+			if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
+				word0(&rv) += P*Exp_msk1;
+				adj.d *= ulp(dval(&rv));
+				if (bc.dsign)
+					dval(&rv) += adj.d;
 				else
-					dval(rv) -= adj;
-				word0(rv) -= P*Exp_msk1;
+					dval(&rv) -= adj.d;
+				word0(&rv) -= P*Exp_msk1;
 				goto cont;
 				}
 #endif /*Sudden_Underflow*/
 #endif /*Avoid_Underflow*/
-			adj *= ulp(dval(rv));
-			if (dsign) {
-				if (word0(rv) == Big0 && word1(rv) == Big1)
+			adj.d *= ulp(&rv);
+			if (bc.dsign) {
+				if (word0(&rv) == Big0 && word1(&rv) == Big1)
 					goto ovfl;
-				dval(rv) += adj;
+				dval(&rv) += adj.d;
 				}
 			else
-				dval(rv) -= adj;
+				dval(&rv) -= adj.d;
 			goto cont;
 			}
 #endif /*Honor_FLT_ROUNDS*/
@@ -2153,25 +3085,25 @@ strtod
 			/* Error is less than half an ulp -- check for
 			 * special case of mantissa a power of two.
 			 */
-			if (dsign || word1(rv) || word0(rv) & Bndry_mask
+			if (bc.dsign || word1(&rv) || word0(&rv) & Bndry_mask
 #ifdef IEEE_Arith
 #ifdef Avoid_Underflow
-			 || (word0(rv) & Exp_mask) <= (2*P+1)*Exp_msk1
+			 || (word0(&rv) & Exp_mask) <= (2*P+1)*Exp_msk1
 #else
-			 || (word0(rv) & Exp_mask) <= Exp_msk1
+			 || (word0(&rv) & Exp_mask) <= Exp_msk1
 #endif
 #endif
 				) {
 #ifdef SET_INEXACT
 				if (!delta->x[0] && delta->wds <= 1)
-					inexact = 0;
+					bc.inexact = 0;
 #endif
 				break;
 				}
 			if (!delta->x[0] && delta->wds <= 1) {
 				/* exact result */
 #ifdef SET_INEXACT
-				inexact = 0;
+				bc.inexact = 0;
 #endif
 				break;
 				}
@@ -2182,62 +3114,72 @@ strtod
 			}
 		if (i == 0) {
 			/* exactly half-way between */
-			if (dsign) {
-				if ((word0(rv) & Bndry_mask1) == Bndry_mask1
-				 &&  word1(rv) == (
+			if (bc.dsign) {
+				if ((word0(&rv) & Bndry_mask1) == Bndry_mask1
+				 &&  word1(&rv) == (
 #ifdef Avoid_Underflow
-			(scale && (y = word0(rv) & Exp_mask) <= 2*P*Exp_msk1)
+			(bc.scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
 		? (0xffffffff & (0xffffffff << (2*P+1-(y>>Exp_shift)))) :
 #endif
 						   0xffffffff)) {
 					/*boundary case -- increment exponent*/
-					word0(rv) = (word0(rv) & Exp_mask)
+					word0(&rv) = (word0(&rv) & Exp_mask)
 						+ Exp_msk1
 #ifdef IBM
 						| Exp_msk1 >> 4
 #endif
 						;
-					word1(rv) = 0;
+					word1(&rv) = 0;
 #ifdef Avoid_Underflow
-					dsign = 0;
+					bc.dsign = 0;
 #endif
 					break;
 					}
 				}
-			else if (!(word0(rv) & Bndry_mask) && !word1(rv)) {
+			else if (!(word0(&rv) & Bndry_mask) && !word1(&rv)) {
  drop_down:
 				/* boundary case -- decrement exponent */
 #ifdef Sudden_Underflow /*{{*/
-				L = word0(rv) & Exp_mask;
+				L = word0(&rv) & Exp_mask;
 #ifdef IBM
 				if (L <  Exp_msk1)
 #else
 #ifdef Avoid_Underflow
-				if (L <= (scale ? (2*P+1)*Exp_msk1 : Exp_msk1))
+				if (L <= (bc.scale ? (2*P+1)*Exp_msk1 : Exp_msk1))
 #else
 				if (L <= Exp_msk1)
 #endif /*Avoid_Underflow*/
 #endif /*IBM*/
+					{
+					if (bc.nd >nd) {
+						bc.uflchk = 1;
+						break;
+						}
 					goto undfl;
+					}
 				L -= Exp_msk1;
 #else /*Sudden_Underflow}{*/
 #ifdef Avoid_Underflow
-				if (scale) {
-					L = word0(rv) & Exp_mask;
+				if (bc.scale) {
+					L = word0(&rv) & Exp_mask;
 					if (L <= (2*P+1)*Exp_msk1) {
 						if (L > (P+2)*Exp_msk1)
 							/* round even ==> */
 							/* accept rv */
 							break;
 						/* rv = smallest denormal */
+						if (bc.nd >nd) {
+							bc.uflchk = 1;
+							break;
+							}
 						goto undfl;
 						}
 					}
 #endif /*Avoid_Underflow*/
-				L = (word0(rv) & Exp_mask) - Exp_msk1;
+				L = (word0(&rv) & Exp_mask) - Exp_msk1;
 #endif /*Sudden_Underflow}}*/
-				word0(rv) = L | Bndry_mask1;
-				word1(rv) = 0xffffffff;
+				word0(&rv) = L | Bndry_mask1;
+				word1(&rv) = 0xffffffff;
 #ifdef IBM
 				goto cont;
 #else
@@ -2245,32 +3187,42 @@ strtod
 #endif
 				}
 #ifndef ROUND_BIASED
-			if (!(word1(rv) & LSB))
+			if (!(word1(&rv) & LSB))
 				break;
 #endif
-			if (dsign)
-				dval(rv) += ulp(dval(rv));
+			if (bc.dsign)
+				dval(&rv) += ulp(&rv);
 #ifndef ROUND_BIASED
 			else {
-				dval(rv) -= ulp(dval(rv));
+				dval(&rv) -= ulp(&rv);
 #ifndef Sudden_Underflow
-				if (!dval(rv))
+				if (!dval(&rv)) {
+					if (bc.nd >nd) {
+						bc.uflchk = 1;
+						break;
+						}
 					goto undfl;
+					}
 #endif
 				}
 #ifdef Avoid_Underflow
-			dsign = 1 - dsign;
+			bc.dsign = 1 - bc.dsign;
 #endif
 #endif
 			break;
 			}
 		if ((aadj = ratio(delta, bs)) <= 2.) {
-			if (dsign)
+			if (bc.dsign)
 				aadj = aadj1 = 1.;
-			else if (word1(rv) || word0(rv) & Bndry_mask) {
+			else if (word1(&rv) || word0(&rv) & Bndry_mask) {
 #ifndef Sudden_Underflow
-				if (word1(rv) == Tiny1 && !word0(rv))
+				if (word1(&rv) == Tiny1 && !word0(&rv)) {
+					if (bc.nd >nd) {
+						bc.uflchk = 1;
+						break;
+						}
 					goto undfl;
+					}
 #endif
 				aadj = 1.;
 				aadj1 = -1.;
@@ -2288,9 +3240,9 @@ strtod
 			}
 		else {
 			aadj *= 0.5;
-			aadj1 = dsign ? aadj : -aadj;
+			aadj1 = bc.dsign ? aadj : -aadj;
 #ifdef Check_FLT_ROUNDS
-			switch(Rounding) {
+			switch(bc.rounding) {
 				case 2: /* towards +infinity */
 					aadj1 -= 0.5;
 					break;
@@ -2303,65 +3255,72 @@ strtod
 				aadj1 += 0.5;
 #endif /*Check_FLT_ROUNDS*/
 			}
-		y = word0(rv) & Exp_mask;
+		y = word0(&rv) & Exp_mask;
 
 		/* Check for overflow */
 
 		if (y == Exp_msk1*(DBL_MAX_EXP+Bias-1)) {
-			dval(rv0) = dval(rv);
-			word0(rv) -= P*Exp_msk1;
-			adj = aadj1 * ulp(dval(rv));
-			dval(rv) += adj;
-			if ((word0(rv) & Exp_mask) >=
+			dval(&rv0) = dval(&rv);
+			word0(&rv) -= P*Exp_msk1;
+			adj.d = aadj1 * ulp(&rv);
+			dval(&rv) += adj.d;
+			if ((word0(&rv) & Exp_mask) >=
 					Exp_msk1*(DBL_MAX_EXP+Bias-P)) {
-				if (word0(rv0) == Big0 && word1(rv0) == Big1)
+				if (word0(&rv0) == Big0 && word1(&rv0) == Big1)
 					goto ovfl;
-				word0(rv) = Big0;
-				word1(rv) = Big1;
+				word0(&rv) = Big0;
+				word1(&rv) = Big1;
 				goto cont;
 				}
 			else
-				word0(rv) += P*Exp_msk1;
+				word0(&rv) += P*Exp_msk1;
 			}
 		else {
 #ifdef Avoid_Underflow
-			if (scale && y <= 2*P*Exp_msk1) {
+			if (bc.scale && y <= 2*P*Exp_msk1) {
 				if (aadj <= 0x7fffffff) {
 					if ((z = aadj) <= 0)
 						z = 1;
 					aadj = z;
-					aadj1 = dsign ? aadj : -aadj;
+					aadj1 = bc.dsign ? aadj : -aadj;
 					}
-				word0(aadj1) += (2*P+1)*Exp_msk1 - y;
+				dval(&aadj2) = aadj1;
+				word0(&aadj2) += (2*P+1)*Exp_msk1 - y;
+				aadj1 = dval(&aadj2);
 				}
-			adj = aadj1 * ulp(dval(rv));
-			dval(rv) += adj;
+			adj.d = aadj1 * ulp(&rv);
+			dval(&rv) += adj.d;
 #else
 #ifdef Sudden_Underflow
-			if ((word0(rv) & Exp_mask) <= P*Exp_msk1) {
-				dval(rv0) = dval(rv);
-				word0(rv) += P*Exp_msk1;
-				adj = aadj1 * ulp(dval(rv));
-				dval(rv) += adj;
+			if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
+				dval(&rv0) = dval(&rv);
+				word0(&rv) += P*Exp_msk1;
+				adj.d = aadj1 * ulp(&rv);
+				dval(&rv) += adj.d;
 #ifdef IBM
-				if ((word0(rv) & Exp_mask) <  P*Exp_msk1)
+				if ((word0(&rv) & Exp_mask) <  P*Exp_msk1)
 #else
-				if ((word0(rv) & Exp_mask) <= P*Exp_msk1)
+				if ((word0(&rv) & Exp_mask) <= P*Exp_msk1)
 #endif
 					{
-					if (word0(rv0) == Tiny0
-					 && word1(rv0) == Tiny1)
+					if (word0(&rv0) == Tiny0
+					 && word1(&rv0) == Tiny1) {
+						if (bc.nd >nd) {
+							bc.uflchk = 1;
+							break;
+							}
 						goto undfl;
-					word0(rv) = Tiny0;
-					word1(rv) = Tiny1;
+						}
+					word0(&rv) = Tiny0;
+					word1(&rv) = Tiny1;
 					goto cont;
 					}
 				else
-					word0(rv) -= P*Exp_msk1;
+					word0(&rv) -= P*Exp_msk1;
 				}
 			else {
-				adj = aadj1 * ulp(dval(rv));
-				dval(rv) += adj;
+				adj.d = aadj1 * ulp(&rv);
+				dval(&rv) += adj.d;
 				}
 #else /*Sudden_Underflow*/
 			/* Compute adj so that the IEEE rounding rules will
@@ -2373,31 +3332,33 @@ strtod
 			 */
 			if (y <= (P-1)*Exp_msk1 && aadj > 1.) {
 				aadj1 = (double)(int)(aadj + 0.5);
-				if (!dsign)
+				if (!bc.dsign)
 					aadj1 = -aadj1;
 				}
-			adj = aadj1 * ulp(dval(rv));
-			dval(rv) += adj;
+			adj.d = aadj1 * ulp(&rv);
+			dval(&rv) += adj.d;
 #endif /*Sudden_Underflow*/
 #endif /*Avoid_Underflow*/
 			}
-		z = word0(rv) & Exp_mask;
+		z = word0(&rv) & Exp_mask;
 #ifndef SET_INEXACT
+		if (bc.nd == nd) {
 #ifdef Avoid_Underflow
-		if (!scale)
+		if (!bc.scale)
 #endif
 		if (y == z) {
 			/* Can we stop now? */
 			L = (Long)aadj;
 			aadj -= L;
 			/* The tolerances below are conservative. */
-			if (dsign || word1(rv) || word0(rv) & Bndry_mask) {
+			if (bc.dsign || word1(&rv) || word0(&rv) & Bndry_mask) {
 				if (aadj < .4999999 || aadj > .5000001)
 					break;
 				}
 			else if (aadj < .4999999/FLT_RADIX)
 				break;
 			}
+		}
 #endif
  cont:
 		Bfree(bb);
@@ -2405,168 +3366,53 @@ strtod
 		Bfree(bs);
 		Bfree(delta);
 		}
+	Bfree(bb);
+	Bfree(bd);
+	Bfree(bs);
+	Bfree(bd0);
+	Bfree(delta);
+#ifndef NO_STRTOD_BIGCOMP
+	if (bc.nd > nd)
+		bigcomp(&rv, s0, &bc);
+#endif
 #ifdef SET_INEXACT
-	if (inexact) {
+	if (bc.inexact) {
 		if (!oldinexact) {
-			word0(rv0) = Exp_1 + (70 << Exp_shift);
-			word1(rv0) = 0;
-			dval(rv0) += 1.;
+			word0(&rv0) = Exp_1 + (70 << Exp_shift);
+			word1(&rv0) = 0;
+			dval(&rv0) += 1.;
 			}
 		}
 	else if (!oldinexact)
 		clear_inexact();
 #endif
 #ifdef Avoid_Underflow
-	if (scale) {
-		word0(rv0) = Exp_1 - 2*P*Exp_msk1;
-		word1(rv0) = 0;
-		dval(rv) *= dval(rv0);
+	if (bc.scale) {
+		word0(&rv0) = Exp_1 - 2*P*Exp_msk1;
+		word1(&rv0) = 0;
+		dval(&rv) *= dval(&rv0);
 #ifndef NO_ERRNO
 		/* try to avoid the bug of testing an 8087 register value */
 #ifdef IEEE_Arith
-		if (!(word0(rv) & Exp_mask))
+		if (!(word0(&rv) & Exp_mask))
 #else
-		if (word0(rv) == 0 && word1(rv) == 0)
+		if (word0(&rv) == 0 && word1(&rv) == 0)
 #endif
 			errno = ERANGE;
 #endif
 		}
 #endif /* Avoid_Underflow */
 #ifdef SET_INEXACT
-	if (inexact && !(word0(rv) & Exp_mask)) {
+	if (bc.inexact && !(word0(&rv) & Exp_mask)) {
 		/* set underflow bit */
-		dval(rv0) = 1e-300;
-		dval(rv0) *= dval(rv0);
+		dval(&rv0) = 1e-300;
+		dval(&rv0) *= dval(&rv0);
 		}
 #endif
- retfree:
-	Bfree(bb);
-	Bfree(bd);
-	Bfree(bs);
-	Bfree(bd0);
-	Bfree(delta);
  ret:
 	if (se)
 		*se = (char *)s;
-	return sign ? -dval(rv) : dval(rv);
-	}
-
- static int
-quorem
-#ifdef KR_headers
-	(b, S) Bigint *b, *S;
-#else
-	(Bigint *b, Bigint *S)
-#endif
-{
-	int n;
-	ULong *bx, *bxe, q, *sx, *sxe;
-#ifdef ULLong
-	ULLong borrow, carry, y, ys;
-#else
-	ULong borrow, carry, y, ys;
-#ifdef Pack_32
-	ULong si, z, zs;
-#endif
-#endif
-
-	n = S->wds;
-#ifdef DEBUG
-	/*debug*/ if (b->wds > n)
-	/*debug*/	Bug("oversize b in quorem");
-#endif
-	if (b->wds < n)
-		return 0;
-	sx = S->x;
-	sxe = sx + --n;
-	bx = b->x;
-	bxe = bx + n;
-	q = *bxe / (*sxe + 1);	/* ensure q <= true quotient */
-#ifdef DEBUG
-	/*debug*/ if (q > 9)
-	/*debug*/	Bug("oversized quotient in quorem");
-#endif
-	if (q) {
-		borrow = 0;
-		carry = 0;
-		do {
-#ifdef ULLong
-			ys = *sx++ * (ULLong)q + carry;
-			carry = ys >> 32;
-			y = *bx - (ys & FFFFFFFF) - borrow;
-			borrow = y >> 32 & (ULong)1;
-			*bx++ = y & FFFFFFFF;
-#else
-#ifdef Pack_32
-			si = *sx++;
-			ys = (si & 0xffff) * q + carry;
-			zs = (si >> 16) * q + (ys >> 16);
-			carry = zs >> 16;
-			y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
-			borrow = (y & 0x10000) >> 16;
-			z = (*bx >> 16) - (zs & 0xffff) - borrow;
-			borrow = (z & 0x10000) >> 16;
-			Storeinc(bx, z, y);
-#else
-			ys = *sx++ * q + carry;
-			carry = ys >> 16;
-			y = *bx - (ys & 0xffff) - borrow;
-			borrow = (y & 0x10000) >> 16;
-			*bx++ = y & 0xffff;
-#endif
-#endif
-			}
-			while(sx <= sxe);
-		if (!*bxe) {
-			bx = b->x;
-			while(--bxe > bx && !*bxe)
-				--n;
-			b->wds = n;
-			}
-		}
-	if (cmp(b, S) >= 0) {
-		q++;
-		borrow = 0;
-		carry = 0;
-		bx = b->x;
-		sx = S->x;
-		do {
-#ifdef ULLong
-			ys = *sx++ + carry;
-			carry = ys >> 32;
-			y = *bx - (ys & FFFFFFFF) - borrow;
-			borrow = y >> 32 & (ULong)1;
-			*bx++ = y & FFFFFFFF;
-#else
-#ifdef Pack_32
-			si = *sx++;
-			ys = (si & 0xffff) + carry;
-			zs = (si >> 16) + (ys >> 16);
-			carry = zs >> 16;
-			y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
-			borrow = (y & 0x10000) >> 16;
-			z = (*bx >> 16) - (zs & 0xffff) - borrow;
-			borrow = (z & 0x10000) >> 16;
-			Storeinc(bx, z, y);
-#else
-			ys = *sx++ + carry;
-			carry = ys >> 16;
-			y = *bx - (ys & 0xffff) - borrow;
-			borrow = (y & 0x10000) >> 16;
-			*bx++ = y & 0xffff;
-#endif
-#endif
-			}
-			while(sx <= sxe);
-		bx = b->x;
-		bxe = bx + n;
-		if (!*bxe) {
-			while(--bxe > bx && !*bxe)
-				--n;
-			b->wds = n;
-			}
-		}
-	return q;
+	return sign ? -dval(&rv) : dval(&rv);
 	}
 
 #ifndef MULTIPLE_THREADS
@@ -2671,10 +3517,10 @@ freedtoa(char *s)
  char *
 dtoa
 #ifdef KR_headers
-	(d, mode, ndigits, decpt, sign, rve)
-	double d; int mode, ndigits, *decpt, *sign; char **rve;
+	(dd, mode, ndigits, decpt, sign, rve)
+	double dd; int mode, ndigits, *decpt, *sign; char **rve;
 #else
-	(double d, int mode, int ndigits, int *decpt, int *sign, char **rve)
+	(double dd, int mode, int ndigits, int *decpt, int *sign, char **rve)
 #endif
 {
  /*	Arguments ndigits, decpt, sign are similar to those
@@ -2711,7 +3557,7 @@ dtoa
 		to hold the suppressed trailing zeros.
 	*/
 
-	int bbits, b2, b5, be, dig, i, ieps, ilim = 0, ilim0, ilim1 = 0,
+	int bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1,
 		j, j1, k, k0, k_check, leftright, m2, m5, s2, s5,
 		spec_case, try_quick;
 	Long L;
@@ -2720,7 +3566,8 @@ dtoa
 	ULong x;
 #endif
 	Bigint *b, *b1, *delta, *mlo, *mhi, *S;
-	double d2, ds, eps;
+	U d2, eps, u;
+	double ds;
 	char *s, *s0;
 #ifdef SET_INEXACT
 	int inexact, oldinexact;
@@ -2746,34 +3593,35 @@ dtoa
 		}
 #endif
 
-	if (word0(d) & Sign_bit) {
+	u.d = dd;
+	if (word0(&u) & Sign_bit) {
 		/* set sign for everything, including 0's and NaNs */
 		*sign = 1;
-		word0(d) &= ~Sign_bit;	/* clear sign bit */
+		word0(&u) &= ~Sign_bit;	/* clear sign bit */
 		}
 	else
 		*sign = 0;
 
 #if defined(IEEE_Arith) + defined(VAX)
 #ifdef IEEE_Arith
-	if ((word0(d) & Exp_mask) == Exp_mask)
+	if ((word0(&u) & Exp_mask) == Exp_mask)
 #else
-	if (word0(d)  == 0x8000)
+	if (word0(&u)  == 0x8000)
 #endif
 		{
 		/* Infinity or NaN */
 		*decpt = 9999;
 #ifdef IEEE_Arith
-		if (!word1(d) && !(word0(d) & 0xfffff))
+		if (!word1(&u) && !(word0(&u) & 0xfffff))
 			return nrv_alloc("Infinity", rve, 8);
 #endif
 		return nrv_alloc("NaN", rve, 3);
 		}
 #endif
 #ifdef IBM
-	dval(d) += 0; /* normalize */
+	dval(&u) += 0; /* normalize */
 #endif
-	if (!dval(d)) {
+	if (!dval(&u)) {
 		*decpt = 1;
 		return nrv_alloc("0", rve, 1);
 		}
@@ -2792,18 +3640,18 @@ dtoa
 		}
 #endif
 
-	b = d2b(dval(d), &be, &bbits);
+	b = d2b(&u, &be, &bbits);
 #ifdef Sudden_Underflow
-	i = (int)(word0(d) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
+	i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
 #else
-	if ((i = (int)(word0(d) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
+	if ((i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
 #endif
-		dval(d2) = dval(d);
-		word0(d2) &= Frac_mask1;
-		word0(d2) |= Exp_11;
+		dval(&d2) = dval(&u);
+		word0(&d2) &= Frac_mask1;
+		word0(&d2) |= Exp_11;
 #ifdef IBM
-		if (j = 11 - hi0bits(word0(d2) & Frac_mask))
-			dval(d2) /= 1 << j;
+		if (j = 11 - hi0bits(word0(&d2) & Frac_mask))
+			dval(&d2) /= 1 << j;
 #endif
 
 		/* log(x)	~=~ log(1.5) + (x-1.5)/1.5
@@ -2840,21 +3688,21 @@ dtoa
 		/* d is denormalized */
 
 		i = bbits + be + (Bias + (P-1) - 1);
-		x = i > 32  ? word0(d) << 64 - i | word1(d) >> i - 32
-			    : word1(d) << 32 - i;
-		dval(d2) = x;
-		word0(d2) -= 31*Exp_msk1; /* adjust exponent */
+		x = i > 32  ? word0(&u) << (64 - i) | word1(&u) >> (i - 32)
+			    : word1(&u) << (32 - i);
+		dval(&d2) = x;
+		word0(&d2) -= 31*Exp_msk1; /* adjust exponent */
 		i -= (Bias + (P-1) - 1) + 1;
 		denorm = 1;
 		}
 #endif
-	ds = (dval(d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
+	ds = (dval(&d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
 	k = (int)ds;
 	if (ds < 0. && ds != k)
 		k--;	/* want k = floor(ds) */
 	k_check = 1;
 	if (k >= 0 && k <= Ten_pmax) {
-		if (dval(d) < tens[k])
+		if (dval(&u) < tens[k])
 			k--;
 		k_check = 0;
 		}
@@ -2893,10 +3741,11 @@ dtoa
 		try_quick = 0;
 		}
 	leftright = 1;
+	ilim = ilim1 = -1;	/* Values for cases 0 and 1; done here to */
+				/* silence erroneous "gcc -Wall" warning. */
 	switch(mode) {
 		case 0:
 		case 1:
-			ilim = ilim1 = -1;
 			i = 18;
 			ndigits = 0;
 			break;
@@ -2930,7 +3779,7 @@ dtoa
 		/* Try to get by with floating-point arithmetic. */
 
 		i = 0;
-		dval(d2) = dval(d);
+		dval(&d2) = dval(&u);
 		k0 = k;
 		ilim0 = ilim;
 		ieps = 2; /* conservative */
@@ -2940,7 +3789,7 @@ dtoa
 			if (j & Bletch) {
 				/* prevent overflows */
 				j &= Bletch - 1;
-				dval(d) /= bigtens[n_bigtens-1];
+				dval(&u) /= bigtens[n_bigtens-1];
 				ieps++;
 				}
 			for(; j; j >>= 1, i++)
@@ -2948,32 +3797,32 @@ dtoa
 					ieps++;
 					ds *= bigtens[i];
 					}
-			dval(d) /= ds;
+			dval(&u) /= ds;
 			}
 		else if ((j1 = -k)) {
-			dval(d) *= tens[j1 & 0xf];
+			dval(&u) *= tens[j1 & 0xf];
 			for(j = j1 >> 4; j; j >>= 1, i++)
 				if (j & 1) {
 					ieps++;
-					dval(d) *= bigtens[i];
+					dval(&u) *= bigtens[i];
 					}
 			}
-		if (k_check && dval(d) < 1. && ilim > 0) {
+		if (k_check && dval(&u) < 1. && ilim > 0) {
 			if (ilim1 <= 0)
 				goto fast_failed;
 			ilim = ilim1;
 			k--;
-			dval(d) *= 10.;
+			dval(&u) *= 10.;
 			ieps++;
 			}
-		dval(eps) = ieps*dval(d) + 7.;
-		word0(eps) -= (P-1)*Exp_msk1;
+		dval(&eps) = ieps*dval(&u) + 7.;
+		word0(&eps) -= (P-1)*Exp_msk1;
 		if (ilim == 0) {
 			S = mhi = 0;
-			dval(d) -= 5.;
-			if (dval(d) > dval(eps))
+			dval(&u) -= 5.;
+			if (dval(&u) > dval(&eps))
 				goto one_digit;
-			if (dval(d) < -dval(eps))
+			if (dval(&u) < -dval(&eps))
 				goto no_digits;
 			goto fast_failed;
 			}
@@ -2982,34 +3831,34 @@ dtoa
 			/* Use Steele & White method of only
 			 * generating digits needed.
 			 */
-			dval(eps) = 0.5/tens[ilim-1] - dval(eps);
+			dval(&eps) = 0.5/tens[ilim-1] - dval(&eps);
 			for(i = 0;;) {
-				L = dval(d);
-				dval(d) -= L;
+				L = dval(&u);
+				dval(&u) -= L;
 				*s++ = '0' + (int)L;
-				if (dval(d) < dval(eps))
+				if (dval(&u) < dval(&eps))
 					goto ret1;
-				if (1. - dval(d) < dval(eps))
+				if (1. - dval(&u) < dval(&eps))
 					goto bump_up;
 				if (++i >= ilim)
 					break;
-				dval(eps) *= 10.;
-				dval(d) *= 10.;
+				dval(&eps) *= 10.;
+				dval(&u) *= 10.;
 				}
 			}
 		else {
 #endif
 			/* Generate ilim digits, then fix them up. */
-			dval(eps) *= tens[ilim-1];
-			for(i = 1;; i++, dval(d) *= 10.) {
-				L = (Long)(dval(d));
-				if (!(dval(d) -= L))
+			dval(&eps) *= tens[ilim-1];
+			for(i = 1;; i++, dval(&u) *= 10.) {
+				L = (Long)(dval(&u));
+				if (!(dval(&u) -= L))
 					ilim = i;
 				*s++ = '0' + (int)L;
 				if (i == ilim) {
-					if (dval(d) > 0.5 + dval(eps))
+					if (dval(&u) > 0.5 + dval(&eps))
 						goto bump_up;
-					else if (dval(d) < 0.5 - dval(eps)) {
+					else if (dval(&u) < 0.5 - dval(&eps)) {
 						while(*--s == '0');
 						s++;
 						goto ret1;
@@ -3022,7 +3871,7 @@ dtoa
 #endif
  fast_failed:
 		s = s0;
-		dval(d) = dval(d2);
+		dval(&u) = dval(&d2);
 		k = k0;
 		ilim = ilim0;
 		}
@@ -3034,22 +3883,22 @@ dtoa
 		ds = tens[k];
 		if (ndigits < 0 && ilim <= 0) {
 			S = mhi = 0;
-			if (ilim < 0 || dval(d) <= 5*ds)
+			if (ilim < 0 || dval(&u) <= 5*ds)
 				goto no_digits;
 			goto one_digit;
 			}
-		for(i = 1;; i++, dval(d) *= 10.) {
-			L = (Long)(dval(d) / ds);
-			dval(d) -= L*ds;
+		for(i = 1;; i++, dval(&u) *= 10.) {
+			L = (Long)(dval(&u) / ds);
+			dval(&u) -= L*ds;
 #ifdef Check_FLT_ROUNDS
 			/* If FLT_ROUNDS == 2, L will usually be high by 1 */
-			if (dval(d) < 0) {
+			if (dval(&u) < 0) {
 				L--;
-				dval(d) += ds;
+				dval(&u) += ds;
 				}
 #endif
 			*s++ = '0' + (int)L;
-			if (!dval(d)) {
+			if (!dval(&u)) {
 #ifdef SET_INEXACT
 				inexact = 0;
 #endif
@@ -3063,8 +3912,8 @@ dtoa
 				  case 2: goto bump_up;
 				  }
 #endif
-				dval(d) += dval(d);
-				if (dval(d) > ds || dval(d) == ds && L & 1) {
+				dval(&u) += dval(&u);
+				if (dval(&u) > ds || (dval(&u) == ds && L & 1)) {
  bump_up:
 					while(*--s == '9')
 						if (s == s0) {
@@ -3129,9 +3978,9 @@ dtoa
 			&& Rounding == 1
 #endif
 				) {
-		if (!word1(d) && !(word0(d) & Bndry_mask)
+		if (!word1(&u) && !(word0(&u) & Bndry_mask)
 #ifndef Sudden_Underflow
-		 && word0(d) & (Exp_mask & ~Exp_msk1)
+		 && word0(&u) & (Exp_mask & ~Exp_msk1)
 #endif
 				) {
 			/* The special case */
@@ -3151,22 +4000,16 @@ dtoa
 #ifdef Pack_32
 	if ((i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0x1f))
 		i = 32 - i;
+#define iInc 28
 #else
 	if (i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0xf)
 		i = 16 - i;
+#define iInc 12
 #endif
-	if (i > 4) {
-		i -= 4;
-		b2 += i;
-		m2 += i;
-		s2 += i;
-		}
-	else if (i < 4) {
-		i += 28;
-		b2 += i;
-		m2 += i;
-		s2 += i;
-		}
+	i = dshift(S, s2);
+	b2 += i;
+	m2 += i;
+	s2 += i;
 	if (b2 > 0)
 		b = lshift(b, b2);
 	if (s2 > 0)
@@ -3217,7 +4060,7 @@ dtoa
 			j1 = delta->sign ? 1 : cmp(b, delta);
 			Bfree(delta);
 #ifndef ROUND_BIASED
-			if (j1 == 0 && mode != 1 && !(word1(d) & 1)
+			if (j1 == 0 && mode != 1 && !(word1(&u) & 1)
 #ifdef Honor_FLT_ROUNDS
 				&& Rounding >= 1
 #endif
@@ -3234,11 +4077,11 @@ dtoa
 				goto ret;
 				}
 #endif
-			if (j < 0 || j == 0 && mode != 1
+			if (j < 0 || (j == 0 && mode != 1
 #ifndef ROUND_BIASED
-							&& !(word1(d) & 1)
+							&& !(word1(&u) & 1)
 #endif
-					) {
+					)) {
 				if (!b->x[0] && b->wds <= 1) {
 #ifdef SET_INEXACT
 					inexact = 0;
@@ -3255,7 +4098,7 @@ dtoa
 				if (j1 > 0) {
 					b = lshift(b, 1);
 					j1 = cmp(b, S);
-					if ((j1 > 0 || j1 == 0 && dig & 1)
+					if ((j1 > 0 || (j1 == 0 && dig & 1))
 					&& dig++ == '9')
 						goto round_9_up;
 					}
@@ -3315,7 +4158,7 @@ dtoa
 #endif
 	b = lshift(b, 1);
 	j = cmp(b, S);
-	if (j > 0 || j == 0 && dig & 1) {
+	if (j > 0 || (j == 0 && dig & 1)) {
  roundoff:
 		while(*--s == '9')
 			if (s == s0) {
@@ -3343,9 +4186,9 @@ dtoa
 #ifdef SET_INEXACT
 	if (inexact) {
 		if (!oldinexact) {
-			word0(d) = Exp_1 + (70 << Exp_shift);
-			word1(d) = 0;
-			dval(d) += 1.;
+			word0(&u) = Exp_1 + (70 << Exp_shift);
+			word1(&u) = 0;
+			dval(&u) += 1.;
 			}
 		}
 	else if (!oldinexact)