install problem on AIX 4.1(?) - strrchr

[Yotam Medini <yotamm at tmai dot com>]

On a an AIX machine:

   curie:13> /bin/uname -a
   AIX curie 1 4 000159135900

Installation of egcs fails in 

xlc -c -DHAVE_LIBBSD=1 -DSTDC_HEADERS=1 -DHAVE_UNISTD_H=1
    -DHAVE_TERMIOS_H=1 -DHAVE_TERMIO_H=1 -DHAVE_STRINGS_H=1
    -DHAVE_STRING_H=1 -DHAVE_VARARGS_H=1 -DHAVE_SYS_TIME_H=1
    -DHAVE_SYS_FILE_H=1 -DHAVE_ALLOCA=1 -DHAVE_SETVBUF=1 -DHAVE_GETCWD=1
    -DHAVE_MEMSET=1 -DHAVE_BZERO=1 -DHAVE_STRCHR=1 -DHAVE_STRCASECMP=1
    -DHAVE_VFPRINTF=1 -DHAVE_VSPRINTF=1 -DHAVE_STRERROR=1
    -DHAVE_SIGPROCMASK=1 -DHAVE_SIGSETMASK=1 -DHAVE_MEMCPY=1
    -DHAVE_MEMMOVE=1 -DHAVE_STRDUP=1 -I. -I. -I./../libtxi install-info.c

"install-info.c", line 625.27: 1506-010 (E) Macro strrchr invoked with a null argument for parameter __s1.
"install-info.c", line 625.27: 1506-041 (E) The invocation of macro strrchr contains fewer arguments than required by the macro definition.
"install-info.c", line 625.18: 1506-275 (S) Unexpected text ',' ignored.
make[6]: *** [install-info.o] Error 1

egcs-970910/texinfo/util/install-info.c: line 265 has:
    extern char *strrchr ();

The reason for failure is that the 'native' /usr/include/string.h has:

   /*
    *   The following macro definitions cause the XLC compiler to inline
    *   these functions whenever possible.
    */

   #ifdef __STR__
   #   define strcpy(__s1,__s2) __strcpy(__s1,__s2)
   #   define strcmp(__s1,__s2) __strcmp(__s1,__s2)

   #   ifndef __STR31__
   #       define strlen(__s1) __strlen(__s1)
   #       define strchr(__s1,__c) __strchr(__s1,__c)
   #       define strrchr(__s1,__c) __strrchr(__s1,__c)
   ....


I wonder, is this 'extern' line necessary. Is there any platform that
does not declare strrchr(.,.) in its string.h?

-- yotam