[Bug sanitizer/87892] New: [9 Regression]: libsanitizer fails to build on CentOS 5.11 (glibc 2.5)

["ubizjak at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87892

            Bug ID: 87892
           Summary: [9 Regression]: libsanitizer fails to build on CentOS
                    5.11 (glibc 2.5)
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ubizjak at gmail dot com
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org, marxin at gcc dot gnu.org
  Target Milestone: ---

Building libsanitizer with old glibc (2.5) fails with:

libtool: compile:  /home/uros/gcc-build/./gcc/xgcc -shared-libgcc
-B/home/uros/gcc-build/./gcc -nostdinc++
-L/home/uros/gcc-build/x86_64-pc-linux-gnu/libstdc++-v3/src
-L/home/uros/gcc-build/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-L/home/uros/gcc-build/x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
-B/home/uros/local/x86_64-pc-linux-gnu/bin/
-B/home/uros/local/x86_64-pc-linux-gnu/lib/ -isystem
/home/uros/local/x86_64-pc-linux-gnu/include -isystem
/home/uros/local/x86_64-pc-linux-gnu/sys-include -D_GNU_SOURCE -D_DEBUG
-D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
-DHAVE_RPC_XDR_H=1 -DHAVE_TIRPC_RPC_XDR_H=0 -I.
-I../../../../git/gcc/libsanitizer/sanitizer_common -I.. -I
../../../../git/gcc/libsanitizer/include -isystem
../../../../git/gcc/libsanitizer/include/system -Wall -W -Wno-unused-parameter
-Wwrite-strings -pedantic -Wno-long-long -fPIC -fno-builtin -fno-exceptions
-fno-rtti -fomit-frame-pointer -funwind-tables -fvisibility=hidden
-Wno-variadic-macros -I../../libstdc++-v3/include
-I../../libstdc++-v3/include/x86_64-pc-linux-gnu
-I../../../../git/gcc/libsanitizer/../libstdc++-v3/libsupc++ -std=gnu++11
-DSANITIZER_LIBBACKTRACE -DSANITIZER_CP_DEMANGLE -I
../../../../git/gcc/libsanitizer/../libbacktrace -I ../libbacktrace -I
../../../../git/gcc/libsanitizer/../include -include
../../../../git/gcc/libsanitizer/libbacktrace/backtrace-rename.h -g -O2
-D_GNU_SOURCE -MT sanitizer_linux_libcdep.lo -MD -MP -MF
.deps/sanitizer_linux_libcdep.Tpo -c
../../../../git/gcc/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc 
-fPIC -DPIC -o .libs/sanitizer_linux_libcdep.o
../../../../git/gcc/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc:
In function ‘__sanitizer::u32 __sanitizer::GetNumberOfCPUs()’:
../../../../git/gcc/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cc:699:10:
error: ‘CPU_COUNT’ was not declared in this scope
  699 |   return CPU_COUNT(&CPUs);
      |          ^~~~~~~~~
gmake[2]: *** [sanitizer_linux_libcdep.lo] Error 1
gmake[2]: Leaving directory
`/home/uros/gcc-build/x86_64-pc-linux-gnu/libsanitizer/sanitizer_common'
gmake[1]: *** [all-recursive] Error 1
gmake[1]: Leaving directory
`/home/uros/gcc-build/x86_64-pc-linux-gnu/libsanitizer'
gmake: *** [all] Error 2