Check in a pristine copy of GCC 4.8.1.

The copy of GCC that we use for Android is still not working for
mingw. Rather than finding all the differences that have crept into
our GCC, just check in a copy from
ftp://ftp.gnu.org/gnu/gcc/gcc-4.9.3/gcc-4.8.1.tar.bz2.

GCC 4.8.1 was chosen because it is what we have been using for mingw
thus far, and the emulator doesn't yet work when upgrading to 4.9.

Bug: http://b/26523949
Change-Id: Iedc0f05243d4332cc27ccd46b8a4b203c88dcaa3

1 files changed, 91 insertions, 0 deletions

diff --git a/gcc-4.8.1/boehm-gc/gc_dlopen.c b/gcc-4.8.1/boehm-gc/gc_dlopen.c
new file mode 100644
index 000000000..4c690edcf
--- /dev/null
+++ b/gcc-4.8.1/boehm-gc/gc_dlopen.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
+ * Copyright (c) 1997 by Silicon Graphics.  All rights reserved.
+ * Copyright (c) 2000 by Hewlett-Packard Company.  All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose,  provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ *
+ * Original author: Bill Janssen
+ * Heavily modified by Hans Boehm and others
+ */
+
+/*
+ * This used to be in dyn_load.c.  It was extracted into a separate file
+ * to avoid having to link against libdl.{a,so} if the client doesn't call
+ * dlopen.  Of course this fails if the collector is in a dynamic
+ * library. -HB
+ */
+
+#include "private/gc_priv.h"
+
+# if (defined(GC_PTHREADS) && !defined(GC_DARWIN_THREADS)) \
+      || defined(GC_SOLARIS_THREADS)
+
+# if defined(dlopen) && !defined(GC_USE_LD_WRAP)
+    /* To support various threads pkgs, gc.h interposes on dlopen by     */
+    /* defining "dlopen" to be "GC_dlopen", which is implemented below.  */
+    /* However, both GC_FirstDLOpenedLinkMap() and GC_dlopen() use the   */
+    /* real system dlopen() in their implementation. We first remove     */
+    /* gc.h's dlopen definition and restore it later, after GC_dlopen(). */
+#   undef dlopen
+# endif
+
+  /* Make sure we're not in the middle of a collection, and make	*/
+  /* sure we don't start any.	Returns previous value of GC_dont_gc.	*/
+  /* This is invoked prior to a dlopen call to avoid synchronization	*/
+  /* issues.  We can't just acquire the allocation lock, since startup 	*/
+  /* code in dlopen may try to allocate.				*/
+  /* This solution risks heap growth in the presence of many dlopen	*/
+  /* calls in either a multithreaded environment, or if the library	*/
+  /* initialization code allocates substantial amounts of GC'ed memory.	*/
+  /* But I don't know of a better solution.				*/
+  static void disable_gc_for_dlopen()
+  {
+    LOCK();
+    while (GC_incremental && GC_collection_in_progress()) {
+	GC_collect_a_little_inner(1000);
+    }
+    ++GC_dont_gc;
+    UNLOCK();
+  }
+
+  /* Redefine dlopen to guarantee mutual exclusion with	*/
+  /* GC_register_dynamic_libraries.			*/
+  /* Should probably happen for other operating	systems, too. */
+
+#include <dlfcn.h>
+
+#ifdef GC_USE_LD_WRAP
+  void * __wrap_dlopen(const char *path, int mode)
+#else
+  void * GC_dlopen(path, mode)
+  GC_CONST char * path;
+  int mode;
+#endif
+{
+    void * result;
+    
+#   ifndef USE_PROC_FOR_LIBRARIES
+      disable_gc_for_dlopen();
+#   endif
+#   ifdef GC_USE_LD_WRAP
+      result = (void *)__real_dlopen(path, mode);
+#   else
+      result = dlopen(path, mode);
+#   endif
+#   ifndef USE_PROC_FOR_LIBRARIES
+      GC_enable(); /* undoes disable_gc_for_dlopen */
+#   endif
+    return(result);
+}
+# endif  /* GC_PTHREADS || GC_SOLARIS_THREADS ... */
+
+
+