[Bug go/81449] New: runtime.inc:782:28: error: field ‘__sem_lock’ has incomplete type

["mfe at live dot de" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81449

            Bug ID: 81449
           Summary: runtime.inc:782:28: error: field ‘__sem_lock’ has
                    incomplete type
           Product: gcc
           Version: 7.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: go
          Assignee: ian at airs dot com
          Reporter: mfe at live dot de
                CC: cmang at google dot com
  Target Milestone: ---

the exact version of GCC:
gcc-7.1.0

the system type:
NetgearReadyNAS Duo (http://netgear.nas-central.org/wiki/Category:ReadyNasDUO)

the options given when GCC was configured/built:
configure CC=/opt/gcc-4.6/bin/gcc CXX=/opt/gcc-4.6/bin/g++
--enable-languages=c,c++,go --prefix=/opt/gcc-7.1  --with-cpu=v7
--with-mpc=/usr/local  --with-mpfr=/usr/local --with-gmp=/usr/local
--with-isl=/usr/local/ --disable-libstdcxx-pch 

the complete command line that triggers the bug;
/usr/local/bin/make

the compiler output (error messages, warnings, etc.);
[...]
/media/gcc-7.1-compiled/./gcc/xgcc -B/media/gcc-7.1-compiled/./gcc/
-B/opt/gcc-7.1/sparc-unknown-linux-gnu/bin/
-B/opt/gcc-7.1/sparc-unknown-linux-gnu/lib/ -isystem
/opt/gcc-7.1/sparc-unknown-linux-gnu/include -isystem
/opt/gcc-7.1/sparc-unknown-linux-gnu/sys-include    -DHAVE_CONFIG_H -I.
-I../../../gcc-7.1.0/libgo  -I ../../../gcc-7.1.0/libgo/runtime
-I../../../gcc-7.1.0/libgo/../libffi/include -I../libffi/include -pthread 
-fexceptions -fnon-call-exceptions -fplan9-extensions  -Wall -Wextra
-Wwrite-strings -Wcast-qual -Werror   -D_GNU_SOURCE -D_LARGEFILE_SOURCE
-D_FILE_OFFSET_BITS=64 -I ../../../gcc-7.1.0/libgo/../libgcc -I
../../../gcc-7.1.0/libgo/../libbacktrace -I ../../gcc/include -fPIC -g -O2 -MT
libgobegin_a-go-main.o -MD -MP -MF .deps/libgobegin_a-go-main.Tpo -c -o
libgobegin_a-go-main.o `test -f 'runtime/go-main.c' || echo
'../../../gcc-7.1.0/libgo/'`runtime/go-main.c
In file included from ../../../gcc-7.1.0/libgo/runtime/runtime.h:113:0,
                 from ../../../gcc-7.1.0/libgo/runtime/go-main.c:17:
./runtime.inc:782:28: error: field ‘__sem_lock’ has incomplete type
  struct __pthread_fastlock __sem_lock;
                            ^~~~~~~~~~
make[4]: *** [Makefile:1580: libgobegin_a-go-main.o] Error 1
make[4]: Leaving directory
'/c/media/gcc-7.1-compiled/sparc-unknown-linux-gnu/libgo'
make[3]: *** [Makefile:2746: all-recursive] Error 1
make[3]: Leaving directory
'/c/media/gcc-7.1-compiled/sparc-unknown-linux-gnu/libgo'
make[2]: *** [Makefile:1344: all] Error 2
make[2]: Leaving directory
'/c/media/gcc-7.1-compiled/sparc-unknown-linux-gnu/libgo'
make[1]: *** [Makefile:20030: all-target-libgo] Error 2
make[1]: Leaving directory '/c/media/gcc-7.1-compiled'
make: *** [Makefile:934: all] Error 2

If this bug is related to #81421, I apologize for the inconvenience and I will
set the bug status to invalid.