[Bug c/26386] New: strdup "implicit declaration" warning when using -ansi

[Bug c/26386] New: strdup "implicit declaration" warning when using -ansi

[parcour at gmail dot com]

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test.c ---------------------------------

#include <string.h>
#include <malloc.h>

int main()
{
    char *s = strdup( "foo" );
    free( s );
    return 0;
}

compile in/out -------------------------

$ gcc -Wall -ansi test.c
test.c: In function ‘main’:
test.c:6: warning: implicit declaration of function ‘strdup’
test.c:6: warning: initialization makes pointer from integer without a cast

gcc -v ---------------------------------

Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,java,f95,ada --enable-java-awt=gtk
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre
--host=i386-redhat-linux
Thread model: posix
gcc version 4.0.2 20051125 (Red Hat 4.0.2-8)

test.i ---------------------------------

# 1 "test.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "test.c"
# 1 "/usr/include/string.h" 1 3 4
# 26 "/usr/include/string.h" 3 4
# 1 "/usr/include/features.h" 1 3 4
# 314 "/usr/include/features.h" 3 4
# 1 "/usr/include/sys/cdefs.h" 1 3 4
# 315 "/usr/include/features.h" 2 3 4
# 337 "/usr/include/features.h" 3 4
# 1 "/usr/include/gnu/stubs.h" 1 3 4



# 1 "/usr/include/bits/wordsize.h" 1 3 4
# 5 "/usr/include/gnu/stubs.h" 2 3 4


# 1 "/usr/include/gnu/stubs-32.h" 1 3 4
# 8 "/usr/include/gnu/stubs.h" 2 3 4
# 338 "/usr/include/features.h" 2 3 4
# 27 "/usr/include/string.h" 2 3 4






# 1 "/usr/lib/gcc/i386-redhat-linux/4.0.2/include/stddef.h" 1 3 4
# 214 "/usr/lib/gcc/i386-redhat-linux/4.0.2/include/stddef.h" 3 4
typedef unsigned int size_t;
# 34 "/usr/include/string.h" 2 3 4




extern void *memcpy (void *__restrict __dest,
       __const void *__restrict __src, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (1, 2)));


extern void *memmove (void *__dest, __const void *__src, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (1, 2)));

# 57 "/usr/include/string.h" 3 4


extern void *memset (void *__s, int __c, size_t __n) __attribute__
((__nothrow__)) __attribute__ ((__nonnull__ (1)));


extern int memcmp (__const void *__s1, __const void *__s2, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));


extern void *memchr (__const void *__s, int __c, size_t __n)
      __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1)));

# 82 "/usr/include/string.h" 3 4


extern char *strcpy (char *__restrict __dest, __const char *__restrict __src)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (1, 2)));

extern char *strncpy (char *__restrict __dest,
        __const char *__restrict __src, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (1, 2)));


extern char *strcat (char *__restrict __dest, __const char *__restrict __src)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (1, 2)));

extern char *strncat (char *__restrict __dest, __const char *__restrict __src,
        size_t __n) __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__
(1, 2)));


extern int strcmp (__const char *__s1, __const char *__s2)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));

extern int strncmp (__const char *__s1, __const char *__s2, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));


extern int strcoll (__const char *__s1, __const char *__s2)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));

extern size_t strxfrm (char *__restrict __dest,
         __const char *__restrict __src, size_t __n)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (2)));

# 165 "/usr/include/string.h" 3 4


extern char *strchr (__const char *__s, int __c)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1)));

extern char *strrchr (__const char *__s, int __c)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1)));

# 181 "/usr/include/string.h" 3 4



extern size_t strcspn (__const char *__s, __const char *__reject)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));


extern size_t strspn (__const char *__s, __const char *__accept)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));

extern char *strpbrk (__const char *__s, __const char *__accept)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));

extern char *strstr (__const char *__haystack, __const char *__needle)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1, 2)));



extern char *strtok (char *__restrict __s, __const char *__restrict __delim)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (2)));




extern char *__strtok_r (char *__restrict __s,
    __const char *__restrict __delim,
    char **__restrict __save_ptr)
     __attribute__ ((__nothrow__)) __attribute__ ((__nonnull__ (2, 3)));
# 240 "/usr/include/string.h" 3 4


extern size_t strlen (__const char *__s)
     __attribute__ ((__nothrow__)) __attribute__ ((__pure__)) __attribute__
((__nonnull__ (1)));

# 254 "/usr/include/string.h" 3 4


extern char *strerror (int __errnum) __attribute__ ((__nothrow__));

# 288 "/usr/include/string.h" 3 4
extern void __bzero (void *__s, size_t __n) __attribute__ ((__nothrow__))
__attribute__ ((__nonnull__ (1)));
# 426 "/usr/include/string.h" 3 4

# 2 "test.c" 2
# 1 "/usr/include/malloc.h" 1 3 4
# 24 "/usr/include/malloc.h" 3 4
# 1 "/usr/lib/gcc/i386-redhat-linux/4.0.2/include/stddef.h" 1 3 4
# 152 "/usr/lib/gcc/i386-redhat-linux/4.0.2/include/stddef.h" 3 4
typedef int ptrdiff_t;
# 326 "/usr/lib/gcc/i386-redhat-linux/4.0.2/include/stddef.h" 3 4
typedef long int wchar_t;
# 25 "/usr/include/malloc.h" 2 3 4
# 46 "/usr/include/malloc.h" 3 4



extern void *malloc (size_t __size) __attribute__ ((__nothrow__)) __attribute__
((__malloc__)) ;


extern void *calloc (size_t __nmemb, size_t __size) __attribute__
((__nothrow__))
       __attribute__ ((__malloc__)) ;



extern void *realloc (void *__ptr, size_t __size) __attribute__ ((__nothrow__))
       __attribute__ ((__malloc__)) __attribute__ ((__warn_unused_result__));


extern void free (void *__ptr) __attribute__ ((__nothrow__));


extern void cfree (void *__ptr) __attribute__ ((__nothrow__));


extern void *memalign (size_t __alignment, size_t __size) __attribute__
((__nothrow__))
       __attribute__ ((__malloc__)) ;


extern void *valloc (size_t __size) __attribute__ ((__nothrow__))
       __attribute__ ((__malloc__)) ;



extern void * pvalloc (size_t __size) __attribute__ ((__nothrow__))
       __attribute__ ((__malloc__)) ;



extern void *(*__morecore) (ptrdiff_t __size);


extern void *__default_morecore (ptrdiff_t __size) __attribute__
((__nothrow__))
       __attribute__ ((__malloc__));



struct mallinfo {
  int arena;
  int ordblks;
  int smblks;
  int hblks;
  int hblkhd;
  int usmblks;
  int fsmblks;
  int uordblks;
  int fordblks;
  int keepcost;
};


extern struct mallinfo mallinfo (void) __attribute__ ((__nothrow__));
# 128 "/usr/include/malloc.h" 3 4
extern int mallopt (int __param, int __val) __attribute__ ((__nothrow__));



extern int malloc_trim (size_t __pad) __attribute__ ((__nothrow__));



extern size_t malloc_usable_size (void *__ptr) __attribute__ ((__nothrow__));


extern void malloc_stats (void) __attribute__ ((__nothrow__));


extern void *malloc_get_state (void) __attribute__ ((__nothrow__));



extern int malloc_set_state (void *__ptr) __attribute__ ((__nothrow__));




extern void (*__malloc_initialize_hook) (void);

extern void (*__free_hook) (void *__ptr, __const void *);

extern void *(*__malloc_hook) (size_t __size, __const void *);

extern void *(*__realloc_hook) (void *__ptr, size_t __size, __const void *);

extern void *(*__memalign_hook) (size_t __alignment, size_t __size, __const
void *);


extern void (*__after_morecore_hook) (void);


extern void __malloc_check_init (void) __attribute__ ((__nothrow__));



# 3 "test.c" 2

int main()
{
    char *s = strdup( "foo" );
    free( s );
    return 0;
}


-- 
           Summary: strdup "implicit declaration" warning when using -ansi
           Product: gcc
           Version: 4.0.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: parcour at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26386

[Bug c/26386] strdup "implicit declaration" warning when using -ansi

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2006-02-20 20:06 -------
This is not a GCC bug, strdup is not ISO C.
What is happening is that GCC is defining STRICT_ANSI and glibc says then you
cannot use another thing besides ISO C headers which means no strdup.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26386

[Bug c/26386] strdup "implicit declaration" warning when using -ansi

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2006-02-20 20:07 -------
Ok, either use -D_GNU_SOURCE or don't use -ansi.  Use -pedantic-errors instead
of -ansi.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26386

[Bug c/26386] strdup "implicit declaration" warning when using -ansi

[parcour at gmail dot com]

------- Comment #3 from parcour at gmail dot com  2006-02-20 22:04 -------
Subject: Re:  strdup "implicit declaration" warning when using -ansi

I see.  Sorry for a needless bug report.  But thank you for your
helpful responses.  I expect
I really will need to use -ansi (--> STRICT_ANSI), so I'll have to do
without strdup.

Joshua Shinavier


On 20 Feb 2006 20:07:13 -0000, pinskia at gcc dot gnu dot org
<gcc-bugzilla@gcc.gnu.org> wrote:
>
>
> ------- Comment #2 from pinskia at gcc dot gnu dot org  2006-02-20 20:07 -------
> Ok, either use -D_GNU_SOURCE or don't use -ansi.  Use -pedantic-errors instead
> of -ansi.
>
>
> --
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26386
>
> ------- You are receiving this mail because: -------
> You reported the bug, or are watching the reporter.
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26386