Redefinition of _FILE_OFFSET_BITS triggers an unusual amount of warnings in Solaris.

[Jonathan Blanchard]

hi,

Spurious redefinition of _FILE_OFFSET_BITS trigger many warnings when
using gcc in Solaris. Adding an undef before redefining would clear
the problem.

It is initially defined in
gcc/lib/gcc/i386-pc-solaris2.11/4.3.2/include-fixed/sys included by
string.h.

#if defined(_LP64)
#ifndef _FILE_OFFSET_BITS
#define _FILE_OFFSET_BITS       64
#endif
#if     _FILE_OFFSET_BITS - 0 != 64
#error  "invalid _FILE_OFFSET_BITS value specified"
#endif
#else   /* _LP64 */
#ifndef _FILE_OFFSET_BITS
#define _FILE_OFFSET_BITS       32
#endif
#if     _FILE_OFFSET_BITS - 0 != 32 && _FILE_OFFSET_BITS - 0 != 64
#error  "invalid _FILE_OFFSET_BITS value specified"
#endif
#endif  /* _LP64 */

And here is the result of the configure script on the subject :

configure:3376: checking for _FILE_OFFSET_BITS value needed for large files
configure:3411: gcc -c -g -O2  conftest.c >&5
conftest.c:14: warning: left shift count >= width of type
conftest.c:14: warning: left shift count >= width of type
conftest.c:16: error: size of array 'off_t_is_large' is negative
configure:3417: $? = 1
configure: failed program was:
| /* confdefs.h.  */
| #define PACKAGE_NAME "Scilab"
| #define PACKAGE_TARNAME "scilab"
| #define PACKAGE_VERSION "5"
| #define PACKAGE_STRING "Scilab 5"
| #define PACKAGE_BUGREPORT "http://bugzilla.scilab.org/";
| /* end confdefs.h.  */
| #include <sys/types.h>
|  /* Check that off_t can represent 2**63 - 1 correctly.
|     We can't simply define LARGE_OFF_T to be 9223372036854775807,
|     since some C++ compilers masquerading as C compilers
|     incorrectly reject 9223372036854775807.  */
| #define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
|   int off_t_is_large[(LARGE_OFF_T % 2147483629 == 721
|                      && LARGE_OFF_T % 2147483647 == 1)
|                     ? 1 : -1];
| int
| main ()
| {
|
|   ;
|   return 0;
| }
configure:3461: gcc -c -g -O2  conftest.c >&5
configure:3467: $? = 0
configure:3485: result: 64



Jonathan Blanchard