[Buildroot] [git commit branch/2022.05.x] package/bdwgc: fix build without NPTL

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=2c2a10f5b4e1474251284d812cc5dad4856b487a
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2022.05.x

Fix the following guile build failure without NPTL raised since the
addition of bdwgc in commit b0476427f6c0036b7803d591a5394923c4b07142 and
https://github.com/ivmai/bdwgc/commit/7896408d4149347588ed0e36319b53bcea70115b:

configure:60776: checking for GC_is_heap_ptr
configure:60776: /home/buildroot/autobuild/instance-2/output-1/host/bin/arm-buildroot-linux-uclibcgnueabi-gcc -std=gnu11 -o conftest  -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64  -O1 -g0  -DHAVE_GC_SET_FINALIZER_NOTIFIER -DHAVE_GC_GET_HEAP_USAGE_SAFE -DHAVE_GC_GET_FREE_SPACE_DIVISOR -DHAVE_GC_SET_FINALIZE_ON_DEMAND -flto -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64  conftest.c -L/home/buildroot/autobuild/instance-2/output-1/host/bin/../arm-buildroot-linux-uclibcgnueabi/sysroot/usr/lib -latomic_ops -lgc -lpthread -ldl  -latomic -lm >&5
/home/buildroot/autobuild/instance-2/output-1/host/lib/gcc/arm-buildroot-linux-uclibcgnueabi/10.3.0/../../../../arm-buildroot-linux-uclibcgnueabi/bin/ld: /home/buildroot/autobuild/instance-2/output-1/host/bin/../arm-buildroot-linux-uclibcgnueabi/sysroot/usr/lib/libgc.so: undefined reference to `pthread_getattr_np'

[...]

In file included from ../libguile/alist.h:26,
                 from ../libguile.h:31,
                 from guile.c:38:
../libguile/pairs.h:205:1: error: conflicting types for 'GC_is_heap_ptr'
  205 | GC_is_heap_ptr (void *ptr)
      | ^~~~~~~~~~~~~~
In file included from ../libguile/bdw-gc.h:48,
                 from ../libguile/gc.h:142,
                 from ../libguile/pairs.h:26,
                 from ../libguile/alist.h:26,
                 from ../libguile.h:31,
                 from guile.c:38:
/home/buildroot/autobuild/instance-2/output-1/host/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/include/gc/gc.h:551:20: note: previous declaration of 'GC_is_heap_ptr' was here
  551 | GC_API int GC_CALL GC_is_heap_ptr(const void *);
      |                    ^~~~~~~~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/819f231a60fc81f9a8dd07bf5411aa9d8f78c3bb

Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
(cherry picked from commit 41d60d016461d90deeaacd31e1f66c6333fcca06)
Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
---
 package/bdwgc/bdwgc.mk | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/package/bdwgc/bdwgc.mk b/package/bdwgc/bdwgc.mk
index d1c9d4dfdc..cefa975998 100644
--- a/package/bdwgc/bdwgc.mk
+++ b/package/bdwgc/bdwgc.mk
@@ -21,6 +21,9 @@ endif
 ifeq ($(BR2_STATIC_LIBS),y)
 BDWGC_CFLAGS_EXTRA += -DGC_NO_DLOPEN
 endif
+ifeq ($(BR2_TOOLCHAIN_HAS_THREADS_NPTL),)
+BDWGC_CFLAGS_EXTRA += -DNO_PTHREAD_GETATTR_NP
+endif
 
 # Ensure we use the system libatomic_ops, and not the internal one.
 BDWGC_CONF_OPTS += --with-libatomic-ops=yes