libstdc++: Do not use fast_float for 16-bit size_t [PR104870]

The preprocessor condition for using fast_float should match the one in
the header, and require at least 32-bit size_t.

libstdc++-v3/ChangeLog:

	PR libstdc++/104870
	* src/c++17/floating_from_chars.cc: Check __SIZE_WIDTH__ >= 32
	before using fast_float.

diff --git a/libstdc++-v3/src/c++17/floating_from_chars.cc b/libstdc++-v3/src/c++17/floating_from_chars.cc
index ba1345db3f2411485821cab97566eacd56e6889a..ba0426b3344ef6bc01fdb48f802fba773f4ad2fd 100644 (file)
--- a/libstdc++-v3/src/c++17/floating_from_chars.cc
+++ b/libstdc++-v3/src/c++17/floating_from_chars.cc
@@ -61,7 +61,8 @@
 extern "C" __ieee128 __strtoieee128(const char*, char**);
 #endif
 
-#if _GLIBCXX_FLOAT_IS_IEEE_BINARY32 && _GLIBCXX_DOUBLE_IS_IEEE_BINARY64
+#if _GLIBCXX_FLOAT_IS_IEEE_BINARY32 && _GLIBCXX_DOUBLE_IS_IEEE_BINARY64 \
+    && __SIZE_WIDTH__ >= 32
 # define USE_LIB_FAST_FLOAT 1
 # if __LDBL_MANT_DIG__ == __DBL_MANT_DIG__
 #  undef USE_STRTOD_FOR_FROM_CHARS