Since commit 56a1a3ab ("Silence GCC's \"cast of pointer to integer of a
different size\" warning", 26-10-2015), sparse has been issuing a macro
redefinition warning for the SIZE_MAX macro. However, gcc did not issue
any such warning.
After commit 56a1a3ab, in terms of the order of #includes and #defines,
the code looked something like:
$ cat -n junk.c
1 #include <stddef.h>
2
3 #define SIZE_MAX ((size_t) -1)
4
5 #include <stdint.h>
6
7 int main(int argc, char *argv[])
8 {
9 return 0;
10 }
$
$ gcc junk.c
$
However, if you compile that file with -Wsystem-headers, then it will
also issue a warning. Having set -Wsystem-headers in CFLAGS, using the
config.mak file, then (on cygwin):
$ make compat/regex/regex.o
CC compat/regex/regex.o
In file included from /usr/lib/gcc/x86_64-pc-cygwin/4.9.3/include/stdint.h:9:0,
from compat/regex/regcomp.c:21,
from compat/regex/regex.c:77:
/usr/include/stdint.h:362:0: warning: "SIZE_MAX" redefined
#define SIZE_MAX (__SIZE_MAX__)
^
In file included from compat/regex/regex.c:69:0:
compat/regex/regex_internal.h:108:0: note: this is the location of the previous definition
# define SIZE_MAX ((size_t) -1)
^
$
The compilation of the compat/regex code is somewhat unusual in that the
regex.c file directly #includes the other c files (regcomp.c, regexec.c
and regex_internal.c). Commit 56a1a3ab added an #include of <stdint.h>
to the regcomp.c file, which results in the redefinition, since this is
included after the regex_internal.h header. This header file contains a
'fallback' definition for SIZE_MAX, in order to support systems which do
not have the <stdint.h> header (the HAVE_STDINT_H macro is not defined).
In order to suppress the warning, we move the #include of <stdint.h>
from regcomp.c to the start of the compilation unit, close to the top
of regex.c, prior to the #include of the regex_internal.h header.
Signed-off-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
bd8f005583