Remove use of emscripten_scan_stack

(refactoring)

Issue #530 (bdwgc).

The code was only enabled by a define (USE_EMSCRIPTEN_SCAN_STACK) and
not needed as the alternative is to just use emscripten_stack_get_base
which is more straight forward.

* os_dep.c [EMSCRIPTEN && USE_EMSCRIPTEN_SCAN_STACK
&& EMSCRIPTEN_ASYNCIFY]: Do not include emscripten.h.
* os_dep.c [EMSCRIPTEN && USE_EMSCRIPTEN_SCAN_STACK
&& EMSCRIPTEN_ASYNCIFY] (emscripten_stack_base, scan_stack_cb): Do not
define.
* os_dep.c [EMSCRIPTEN] (GC_get_main_stack_base): Always use
emscripten_stack_get_base().

1 files changed, 2 insertions, 22 deletions

diff --git a/os_dep.c b/os_dep.c
index 8be9459f..be6776a3 100644
--- a/os_dep.c
+++ b/os_dep.c
@@ -1199,31 +1199,11 @@ GC_INNER size_t GC_page_size = 0;
   }
 # define GET_MAIN_STACKBASE_SPECIAL
 #elif defined(EMSCRIPTEN)
-
-# if defined(USE_EMSCRIPTEN_SCAN_STACK) && defined(EMSCRIPTEN_ASYNCIFY)
-    /* According to the documentation, emscripten_scan_stack() is only  */
-    /* guaranteed to be available when building with ASYNCIFY.          */
-#   include <emscripten.h>
-
-    static void *emscripten_stack_base;
-
-    static void scan_stack_cb(void *begin, void *end)
-    {
-      (void)begin;
-      emscripten_stack_base = end;
-    }
-# else
-#   include <emscripten/stack.h>
-# endif
+# include <emscripten/stack.h>
 
   ptr_t GC_get_main_stack_base(void)
   {
-#   if defined(USE_EMSCRIPTEN_SCAN_STACK) && defined(EMSCRIPTEN_ASYNCIFY)
-      emscripten_scan_stack(scan_stack_cb);
-      return (ptr_t)emscripten_stack_base;
-#   else
-      return (ptr_t)emscripten_stack_get_base();
-#   endif
+    return (ptr_t)emscripten_stack_get_base();
   }
 # define GET_MAIN_STACKBASE_SPECIAL
 #elif !defined(AMIGA) && !defined(HAIKU) && !defined(OS2) \