Update bdwgc (#45)

buildtools/bdwgc/Dockerfile

@@ -5,15 +5,13 @@ FROM ghcr.io/webassembly/wasi-sdk:wasi-sdk-20
 
 RUN apt-get -y update && apt-get -y install curl patch
 
-RUN mkdir -p /bdwgc && curl -L https://github.com/ivmai/bdwgc/archive/1d9826992aa2a2783c9badbacddae70fdf7fffee.tar.gz | tar -xz --strip-components 1 -C /bdwgc
+RUN mkdir -p /bdwgc && curl -L https://github.com/ivmai/bdwgc/archive/a753bcb459649d20331d9c9f1dba94588ef56829.tar.gz | tar -xz --strip-components 1 -C /bdwgc
 WORKDIR /bdwgc
 ADD bdwgc.patch bdwgc.patch
 RUN patch -p1 < bdwgc.patch
 RUN ./autogen.sh
 
-# While signals aren't actually used the header file is included unconditionally. We can enable the header file
-# without linking the actual signals library because the functions aren't called.
-ENV CFLAGS -O3 -D_WASI_EMULATED_SIGNAL ${CFLAGS}
+ENV CFLAGS -O3 ${CFLAGS}
 
 # host is required by configure but not used so set it arbitrarily
 RUN ./configure --disable-threads --disable-shared --disable-gcj-support --disable-java-finalization --disable-atomic-uncollectible --host=i686-pc-linux-gnu

buildtools/bdwgc/bdwgc.patch

@@ -11,16 +11,3 @@ index 6970e6f2..a3af3824 100644
  #     if defined(GC_THREADS) && !defined(CPPCHECK)
  #       error No threads support yet
  #     endif
-@@ -3008,10 +3010,10 @@ EXTERN_C_BEGIN
-
- /* Whether GC_page_size is to be set to a value other than page size.   */
- #if defined(CYGWIN32) && (defined(MPROTECT_VDB) || defined(USE_MUNMAP)) \
--    || (!defined(ANY_MSWIN) && !defined(USE_MMAP) \
-+    || (!defined(ANY_MSWIN) && !defined(WASI) && !defined(USE_MMAP) \
-         && (defined(GC_DISABLE_INCREMENTAL) || defined(DEFAULT_VDB)))
-   /* Cygwin: use the allocation granularity instead.                    */
--  /* Other than Windows: use HBLKSIZE instead (unless mmap() is used).  */
-+  /* Other than Windows or WASI: use HBLKSIZE instead (unless mmap() is used).  */
- # define ALT_PAGESIZE_USED
- # ifndef GC_NO_VALLOC
-     /* Nonetheless, we need the real page size is some extra functions. */