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

base/strings/string_number_conversions_unittest.cc

Index: base/strings/string_number_conversions_unittest.cc
diff --git a/base/strings/string_number_conversions_unittest.cc b/base/strings/string_number_conversions_unittest.cc
index 0576302a0798c98329531d27370a9bd15488ebdf..728537440f3d8292a4d63d30f7315f33d6c54826 100644
--- a/base/strings/string_number_conversions_unittest.cc
+++ b/base/strings/string_number_conversions_unittest.cc
@@ -890,4 +890,25 @@ TEST(StringNumberConversionsTest, StrtodFailures) {
   }
 }
 
+TEST(StringNumberConversionsTest, StringToDoubleBugs) {
+  static const struct {
+    std::string input;
+    double output;
+    bool success;
+  } cases[] = {
+      // crbug.com/588726 timeout
+      {"-0.0010000000000000000000000000000000000000001e-256",
+       -1.0000000000000001e-259, true},
+  };
+
+  for (size_t i = 0; i < arraysize(cases); ++i) {

[scottmg, 2016/09/23 18:12:40]

Since there's only one case, it would be clearer to just have this call the
functions and EXPECT directly without a loop. And perhaps rename the test to
something like StringToDoubleHangBug588726.

[kcwu, 2016/09/23 19:23:06]

Done.

+    double output;
+    errno = 1;
+    EXPECT_EQ(cases[i].success, StringToDouble(cases[i].input, &output));
+    if (cases[i].success)
+      EXPECT_EQ(1, errno) << i;  // confirm that errno is unchanged.
+    EXPECT_DOUBLE_EQ(cases[i].output, output);
+  }
+}
+
 }  // namespace base