[Bug bootstrap/54292] New: Errors due to conflicting strsignal headers

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54292

             Bug #: 54292
           Summary: Errors due to conflicting strsignal headers
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: tobi@gcc.gnu.org
            Target: Darwin


This resembles PR31776.  My build from current HEAD fails with
g++ -c   -g -DIN_GCC   -fno-exceptions -fno-rtti -W -Wall -Wwrite-strings
-Wcast-qual -Wmissing-format-attribute -pedantic -Wno-long-long
-Wno-variadic-macros -Wno-overlength-strings -fno-common  -DHAVE_CONFIG_H
-DGENERATOR_FILE -I. -Ibuild -I../../gcc -I../../gcc/build
-I../../gcc/../include -I./../intl -I../../gcc/../libcpp/include
-I/Users/tobi/src/gcc/build/./gmp -I/Users/tobi/src/gcc/gmp
-I/Users/tobi/src/gcc/build/./mpfr -I/Users/tobi/src/gcc/mpfr
-I/Users/tobi/src/gcc/mpc/src  -I../../gcc/../libdecnumber
-I../../gcc/../libdecnumber/dpd -I../libdecnumber    \
                -o build/genconstants.o ../../gcc/genconstants.c
In file included from /usr/include/sys/wait.h:117,
                 from /usr/include/stdlib.h:65,
                 from ../../gcc/system.h:228,
                 from ../../gcc/genconstants.c:29:
/usr/include/sys/resource.h:89: error: declaration does not declare anything
In file included from ../../gcc/genconstants.c:29:
../../gcc/system.h:499: error: declaration of C function 'const char*
strsignal(int)' conflicts with
/usr/include/string.h:144: error: previous declaration 'char* strsignal(int)'
here
make[3]: *** [build/genconstants.o] Error 1
make[2]: *** [all-stage1-gcc] Error 2
make[1]: *** [stage1-bubble] Error 2
make: *** [all] Error 2

I'm using an in-tree gmp, mpfr etc setup with contrib/download_prerequisites. 
I mention this because in gcc/config.log (attached) I see that the strsignal
configure tests apparently got confused by the location of gmp.h.