On Wed Apr 16, 2014 00:48:00 Gerald Pfeifer wrote:
Building git head with GCC development sources (soon to be GCC 4.9.0) gives me the following warnings
../msvcp90/msvcp90.h:529:75: warning: right-hand operand of comma expression has no effect [-Wunused-value] ../msvcp90/msvcp90.h:530:77: warning: right-hand operand of comma expression has no effect [-Wunused-value]
several times.
Digging into this in more detail I see
../msvcp90/ios.c: In function 'basic_streambuf_char__Xsgetn_s': ../msvcp90/msvcp90.h:529:75: warning: right-hand operand of comma expression has no effect [-Wunused-value] #define memcpy_s( dst, size, src, count ) (memcpy( (dst), (src), (count) ), 0) ^ ../msvcp90/ios.c:1218:13: note: in expansion of macro 'memcpy_s' memcpy_s(ptr+copied, size, *this->prpos, chunk); ^
Someone must have written that code intentionally, so I am wondering how to best address this.
Gerald
memcpy_s() returns an errno_t so the author tried to force returning zero (no error).
A simple replacement (still without any checks memcpy_s does) would be:
#define memcpy_s( dst, size, src, count ) (!memcpy( (dst), (src), (count) ))
Paul