AC_CHECK_FUNCS and gcc with -Werror

[Steffen Dettmer]

Hi,

in configure.in I have:

AC_CHECK_FUNCS(printf)

together with some

------------------------------------------------------------------->8=======
AC_DEFUN([IC_ENABLE_ERRORS],[
  AC_ARG_ENABLE(errors,
    [ --enable-errors[=ARG]         Enable error mode
        (warnings are errors) [ARG=no]],
  ....
  if test x$enable_errors = xyes ; then
    case $CC in
      dnl Just in case someone would have a non-gcc "thingcc", don't match *gcc
      gcc|*-gcc)
        CFLAGS="$CFLAGS -Werror";
        ;;
=======8<-------------------------------------------------------------------



In config.log then:

configure:11204: gcc -o conftest  -Wall -Wmissing-prototypes
-fstrict-aliasing -D_GNU_SOURCE -ansi -ggdb -D_REENTRANT -Werror
-ggdb conftest
.c  -lpthread >&5
cc1: warnings being treated as errors
conftest.c:67: warning: conflicting types for built-in function 'printf'

what to do best here?

oki,

Steffen



------------------------------------------------------------------->8=======
configure:11204: gcc -o conftest  -Wall -Wmissing-prototypes
-fstrict-aliasing -D_GNU_SOURCE -ansi -ggdb -D_REENTRANT -Werror
-ggdb conftest
.c  -lpthread >&5
cc1: warnings being treated as errors
conftest.c:67: warning: conflicting types for built-in function 'printf'
configure:11204: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_XXXXXXX
| #define PACKAGE_XXXXXXXXXX
| #define PACKAGE_XXXXXXXXXX
| #define PACKAGE_XXXXXXXXX
| #define PACKAGE_XXXXXXXXXXXX
| #define PACKAGE_XXXXXX
| #define PACKAGE XXXXXXX
| #define VERSION XXXXXXX
| #define linux 1
| #define unix 1
| #define DEBUG 1
| #define ENABLE_LOCATED_MESSAGES 1
| #define CBASE_GENSRC_ERROR_NAMES 1
| #define CLOG_ENABLE_LOW_LEVEL_MESSAGES 1
| #define ENABLE_MALLOC_TRACE 1
| #define ENABLE_UNITTESTS 1
| #define HAVE_CONFIG_SYS_H 1
| #define ENABLE_CCSLOT_LOADER 1
| #define THREADSAFE 1
| #define HAVE_LIBPTHREAD 1
| #define HAVE_PTHREAD_H 1
| #define ENABLE_MULTITHREAD 1
| #define _FILE_OFFSET_BITS 64
| #define STDC_HEADERS 1
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_MEMORY_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_ERRNO_H 1
| #define HAVE_TIME_H 1
| #define HAVE_CTYPE_H 1
| #define HAVE_TERMIOS_H 1
| #define HAVE_TCSETATTR 1
| #define HAVE_SYS_SELECT_H 1
| #define HAVE_SELECT 1
| #define HAVE_LOCALTIME_R 1
| /* end confdefs.h.  */
| /* Define printf to an innocuous variant, in case <limits.h> declares printf.
|    For example, HP-UX 11i <limits.h> declares gettimeofday.  */
| #define printf innocuous_printf
|
| /* System header to define __stub macros and hopefully few prototypes,
|     which can conflict with char printf (); below.
|     Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
|     <limits.h> exists even on freestanding compilers.  */
|
| #ifdef __STDC__
| # include <limits.h>
| #else
| # include <assert.h>
| #endif
|
| #undef printf
|
| /* Override any GCC internal prototype to avoid an error.
|    Use char because int might match the return type of a GCC
|    builtin and then its argument prototype would still apply.  */
| #ifdef __cplusplus
| extern "C"
| #endif
| char printf ();
| /* The GNU C library defines this for functions which it implements
|     to always fail with ENOSYS.  Some functions are actually named
|     something starting with __ and the normal name is an alias.  */
| #if defined __stub_printf || defined __stub___printf
| choke me
| #endif
|
| int
| main ()
| {
| return printf ();
|   ;
|   return 0;
| }
configure:11204: result: no
configure:11215: checking for psyPeripheralResultWait