Serious problem with default headers and C++.

[Akim Demaille]

| Dear all,
| I got some messages when running configure of the foillowing type
| configure: WARNING: cstdio: present but cannot be compiled
| configure: WARNING: cstdio: check for missing prerequisite headers?
| configure: WARNING: cstdio: proceeding with the preprocessor's result
| configure: WARNING:     ## ------------------------------------ ##
| configure: WARNING:     ## Report this to address@hidden ##
| configure: WARNING:     ## ------------------------------------ ##
| 
| Attached is the config.log
| 
| I will try to see myself what I can do with
| 
| cc-1035 CC: WARNING File = /usr/include/CC/cstdio, Line = 4
|   #error directive:  This header requires the -LANG:libc_in_namespace_std
| option
| 
|   #error This header requires the -LANG:libc_in_namespace_std option
|    ^
| 
| But actually the compiler does not recognise the
| -LANG:libc_in_namespace_std option !

Wow :(  This is a serious problem.  I should have thought about this
issue before: the default headers should depend upon the current
language...


| configure:3331: CC -c -64 -mips4 -O3 -LANG:std -LANG:restrict 
-no_auto_include -I/home/u4/patrickg/include -I/home/u4/patrickg/include  
conftest.cc >&5
| cc-1035 CC: WARNING File = /usr/include/CC/cstdio, Line = 4
|   #error directive:  This header requires the -LANG:libc_in_namespace_std 
option
| 
|   #error This header requires the -LANG:libc_in_namespace_std option
|    ^
| 
| cc-1229 CC: ERROR File = /usr/include/internal/stdio_core.h, Line = 220
|   The redeclaration of type name "__file_s" (declared at line 183 of
|           "/opt/MIPSpro/7.3.1.3/usr/include/stdio.h") is invalid.
| 
|   __file_s
|   ^
| 
| #line 3320 "configure"
| /* confdefs.h.  */
| 
| #define PACKAGE_NAME ""
| #define PACKAGE_TARNAME ""
| #define PACKAGE_VERSION ""
| #define PACKAGE_STRING ""
| #define PACKAGE_BUGREPORT ""
| #define PACKAGE "C++"
| #define VERSION "1.0"
| #define HAVE_BLITZ 1
| #define HAVE_FFTW_FFT 1
| #ifdef __cplusplus
| #include <stdlib.h>
| #endif
| #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_UNISTD_H 1
| #define HAVE_CERRNO 1
| /* end confdefs.h.  */
| #include <stdio.h>
| #if HAVE_SYS_TYPES_H
| # include <sys/types.h>
| #endif
| #if HAVE_SYS_STAT_H
| # include <sys/stat.h>
| #endif
| #if STDC_HEADERS
| # include <stdlib.h>
| # include <stddef.h>
| #else
| # if HAVE_STDLIB_H
| #  include <stdlib.h>
| # endif
| #endif
| #if HAVE_STRING_H
| # if !STDC_HEADERS && HAVE_MEMORY_H
| #  include <memory.h>
| # endif
| # include <string.h>
| #endif
| #if HAVE_STRINGS_H
| # include <strings.h>
| #endif
| #if HAVE_INTTYPES_H
| # include <inttypes.h>
| #else
| # if HAVE_STDINT_H
| #  include <stdint.h>
| # endif
| #endif
| #if HAVE_UNISTD_H
| # include <unistd.h>
| #endif
| #include <cstdio>



May I ask you to try to compile the following programs?  Thanks a lot!
(PS/ What package were you compiling?).


1.
     #include <cstdio>


2.
     #include <stdio.h>


3. 
     #include <stdio.h>
     #include <cstdio>