lib/fcntl.in.h fails on AIX 6.1

[Albert Chin]

lib/clean-temp.c has:
  ...
  #include <errno.h>
  #include <fcntl.h>

and lib/fcntl.in.h has:
  #ifndef _GL_FCNTL_H

  @PRAGMA_SYSTEM_HEADER@

  #include <sys/types.h>
  #include <sys/stat.h>
  #include <unistd.h>
  /* The include_next requires a split double-inclusion guard.  */
  address@hidden@ @NEXT_FCNTL_H@

On AIX 5.3:
  $ cd /tmp/z
  $ cat clean-temp.c
#include <fcntl.h>
  $ xlc -I. -E clean-temp.c >/dev/null
  [[ clean compile ]]

On AIX 6.1:
  $ cd /tmp/z
  $ cat clean-temp.c
#include <fcntl.h>
  $ xlc -I. -E clean-temp.c >/dev/null
  "./fcntl.h", line 25: 1506-299 (S) Maximum #include nesting depth of 255 has 
been exceeded.
  "./fcntl.h", line 26: 1506-299 (S) Maximum #include nesting depth of 255 has 
been exceeded.
  "./fcntl.h", line 27: 1506-299 (S) Maximum #include nesting depth of 255 has 
been exceeded.
  "./fcntl.h", line 29: 1506-299 (S) Maximum #include nesting depth of 255 has 
been exceeded.

This is with the IBM v9.0 C compiler. To determine exactly what files
are being included by the compiler:
  $ xlc -I. -qsource -qshowinc clean-temp.c
This generates clean-temp.lst in the existing directory, showing what
files are included. From AIX 5.3:
  $ xlc -I. -qsource -qshowinc clean-temp.c
  $ egrep -e '| #include' clean-temp.lst | egrep -e '<fcntl.h>'
        1 | #include <fcntl.h>
  1    29 | #include_next <fcntl.h>

>From AIX 6.1:
  $ xlc -I. -qsource -qshowinc clean-temp.c
  $ egrep -e '| #include' clean-temp.lst | egrep -e '<fcntl.h>'
        1 | #include <fcntl.h>
  1    29 | #include_next <fcntl.h>
 22    29 | #include_next <fcntl.h>
 26    29 | #include_next <fcntl.h>
 30    29 | #include_next <fcntl.h>
 34    29 | #include_next <fcntl.h>
 38    29 | #include_next <fcntl.h>
 42    29 | #include_next <fcntl.h>
 46    29 | #include_next <fcntl.h>
 50    29 | #include_next <fcntl.h>
 54    29 | #include_next <fcntl.h>
 58    29 | #include_next <fcntl.h>
 62    29 | #include_next <fcntl.h>
    ...

Compiler bug? It seems like #include_next isn't working. Oddly, if I
modify fcntl.h so it's just:
  #include_next <fcntl.h>
then everything works. But, if I precede the #include_next with other
#include directives, the error above occurs. Definitely seems like a
compiler bug. The #include directive seems to be resetting the order of
the search paths.

-- 
albert chin (address@hidden)