[Bug bootstrap/47902] Bootstrap failure: libiberty/regex.c: error: two or more data types in declaration specifiers

["skunk at iskunk dot org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47902

--- Comment #4 from Daniel Richard G. <skunk at iskunk dot org> 2011-02-28 21:59:28 UTC ---
Okay, did some more digging.

So I see that the ac_fn_c_check_type function actually tries a test compilation
first with sizeof(foo_t), and then sizeof((foo_t)), and the test succeeds only
if the first succeeds and the latter fails. So this is actually working as it
should---I'd missed that the test log I pasted in shows pid_t being found
successfully.

The real test failure in config.log is as follows:

configure:5203: checking for pid_t
configure:5203:  /tmp/gcc-4.5.2-build/./prev-gcc/xgcc
-B/tmp/gcc-4.5.2-build/./prev-gcc/ -B/opt/tg/powerpc-ibm-aix4.3.2.0/bin/
-B/opt/tg/powerpc-ibm-aix4.3.2.0/bin/ -B/opt/tg/powerpc-ibm-aix4.3.2.0/lib/
-isystem /opt/tg/powerpc-ibm-aix4.3.2.0/include -isystem
/opt/tg/powerpc-ibm-aix4.3.2.0/sys-include    -c -g -O2  conftest.c >&5
In file included from conftest.c:71:0:
/tmp/gcc-4.5.2-build/./prev-gcc/include/stdint.h:72:29: error: conflicting
types for 'int_fast16_t'
/usr/include/sys/inttypes.h:143:18: note: previous declaration of
'int_fast16_t' was here
/tmp/gcc-4.5.2-build/./prev-gcc/include/stdint.h:75:29: error: conflicting
types for 'uint_fast8_t'
/usr/include/sys/inttypes.h:145:18: note: previous declaration of
'uint_fast8_t' was here
/tmp/gcc-4.5.2-build/./prev-gcc/include/stdint.h:76:30: error: conflicting
types for 'uint_fast16_t'
/usr/include/sys/inttypes.h:146:18: note: previous declaration of
'uint_fast16_t' was here
configure:5203: $? = 1

Which is basically bug #47907.

I notice that the test for pid_t fails if HAVE_STDINT_H is #defined, and
succeeds otherwise.