Make it compile with -Werror on gcc 4.6

patches/gcc46.patch

Index: patches/gcc46.patch
diff --git a/patches/gcc46.patch b/patches/gcc46.patch
new file mode 100644
index 0000000000000000000000000000000000000000..cf4275712869dd838fa0283705d17da9c4608d38
--- /dev/null
+++ b/patches/gcc46.patch
@@ -0,0 +1,20 @@
+diff --git a/public/common/unicode/unistr.h b/public/common/unicode/unistr.h
+index 57ea346..9aba6f0 100644
+--- a/public/common/unicode/unistr.h
++++ b/public/common/unicode/unistr.h
+@@ -4023,6 +4023,7 @@ UnicodeString::replace(int32_t start,
+   int32_t count = 0;
+   UBool isError = FALSE;
+   U16_APPEND(buffer, count, U16_MAX_LENGTH, srcChar, isError);
++  (void) isError;
+   return doReplace(start, _length, buffer, 0, count);
+ }
+ 
+@@ -4326,6 +4327,7 @@ UnicodeString::append(UChar32 srcChar) {
+   int32_t _length = 0;
+   UBool isError = FALSE;
+   U16_APPEND(buffer, _length, U16_MAX_LENGTH, srcChar, isError);
++  (void) isError;
+   return doReplace(length(), 0, buffer, 0, _length);
+ }
+