On Fri, Oct 24, 2014 at 03:41:48PM +0200, Ard Biesheuvel wrote:
On 24 October 2014 15:27, Arnd Bergmann arnd@arndb.de wrote:
On Friday 24 October 2014 13:50:05 Ard Biesheuvel wrote:
On 24 October 2014 13:37, Arnd Bergmann arnd@arndb.de wrote:
On Friday 24 October 2014 12:59:40 Ard Biesheuvel wrote:
On 24 October 2014 12:52, Russell King - ARM Linux linux@arm.linux.org.uk wrote:
On Fri, Oct 24, 2014 at 12:49:50PM +0200, Arnd Bergmann wrote: > > 1 drivers/video/fbdev/sm501fb.c:245:2: warning: format '%zd' expects argument of type 'signed size_t', but argument 8 has type 'size_t' [-Wformat=] > > 1 mm/percpu.c:895:3: warning: format '%zu' expects argument of type 'size_t', but argument 2 has type 'unsigned int' [-Wformat=] > > 1 mm/percpu.c:895:3: warning: format '%zu' expects argument of type 'size_t', but argument 3 has type 'unsigned int' [-Wformat=] > > The warnings are completely unchanged, still 249 unique warnings involving size_t, > using this patch:
That's probably because the compiler is expecting size_t to be typedef'd to __SIZE_TYPE__ and isn't expecting anyone to change it.
Indeed, I wouldn't expect the printf format validation code inside GCC to care about the actual values of macros and typedefs. Could someone dump the builtin #define's of that compiler? For instance, my bare metal 4.9 BE GCC gives me
$ /usr/local/gcc-linaro-armeb-none-eabi-4.9-2014.06_linux/bin/armeb-none-eabi-gcc -E -dM - <<<"" |grep _TYPE__ #define __UINT_LEAST8_TYPE__ unsigned char #define __SIG_ATOMIC_TYPE__ int #define __UINTMAX_TYPE__ long long unsigned int #define __INT_FAST16_TYPE__ int #define __INT_FAST64_TYPE__ long long int #define __UINT8_TYPE__ unsigned char #define __INT_FAST32_TYPE__ int #define __UINT_LEAST16_TYPE__ short unsigned int #define __SIZE_TYPE__ unsigned int #define __INT8_TYPE__ signed char #define __INT_LEAST16_TYPE__ short int #define __UINT_LEAST64_TYPE__ long long unsigned int #define __UINT_FAST16_TYPE__ unsigned int #define __CHAR16_TYPE__ short unsigned int #define __INT_LEAST64_TYPE__ long long int #define __INT16_TYPE__ short int #define __INT_LEAST8_TYPE__ signed char #define __INTPTR_TYPE__ int #define __UINT16_TYPE__ short unsigned int #define __WCHAR_TYPE__ unsigned int #define __UINT_FAST64_TYPE__ long long unsigned int #define __INT64_TYPE__ long long int #define __WINT_TYPE__ unsigned int #define __UINT_LEAST32_TYPE__ long unsigned int #define __INT_LEAST32_TYPE__ long int #define __UINT64_TYPE__ long long unsigned int #define __INT_FAST8_TYPE__ int #define __UINT_FAST32_TYPE__ unsigned int #define __CHAR32_TYPE__ long unsigned int #define __INT32_TYPE__ long int #define __INTMAX_TYPE__ long long int #define __PTRDIFF_TYPE__ int #define __UINT32_TYPE__ long unsigned int #define __UINTPTR_TYPE__ unsigned int #define __UINT_FAST8_TYPE__ unsigned int
What is surprising here is that __SIZE_TYPE__ is int not long. Could we in fact be dealing with a 4.9 bare metal GCC bug here?
This is what I get on every arm gcc version on my system, all glibc or uClibc targetted, compared to yours:
#define __UINT_FAST64_TYPE__ long long unsigned int #define __INT64_TYPE__ long long int #define __WINT_TYPE__ unsigned int -#define __UINT_LEAST32_TYPE__ long unsigned int -#define __INT_LEAST32_TYPE__ long int +#define __UINT_LEAST32_TYPE__ unsigned int +#define __INT_LEAST32_TYPE__ int #define __UINT64_TYPE__ long long unsigned int -#define __INT_FAST8_TYPE__ int +#define __INT_FAST8_TYPE__ signed char #define __UINT_FAST32_TYPE__ unsigned int -#define __CHAR32_TYPE__ long unsigned int -#define __INT32_TYPE__ long int +#define __CHAR32_TYPE__ unsigned int +#define __INT32_TYPE__ int #define __INTMAX_TYPE__ long long int #define __PTRDIFF_TYPE__ int -#define __UINT32_TYPE__ long unsigned int +#define __UINT32_TYPE__ unsigned int #define __UINTPTR_TYPE__ unsigned int -#define __UINT_FAST8_TYPE__ unsigned int +#define __UINT_FAST8_TYPE__ unsigned char
So no __SiZE_TYPE__ then? That's surprising ...
Sorry for being unclear here: this is only the diff between my version and yours, so everything that is not listed above __UINT_FAST64_TYPE__ is the same on both compilers.
Ah, ok. So apparently, size_t is not ambiguous between bare metal and glibc GCC, so we are looking at something else here.
GCC complains about the format specifier being wrong. %zu/%zd are the correct specifiers for variables of type size_t/ssize_t, so wherever a size_t or ssize_t is used as parameter it should have a corresponding %zu or %zd specifier.
Why not just fix it properly instead of mucking about with the size_t typedef?
Thierry