From fe5d1b892a7150e1108c4f96844b29803ccd70dd Mon Sep 17 00:00:00 2001
From: theraven <theraven@72102866-910b-0410-8b05-ffd578937521>
Date: Sat, 28 May 2011 14:38:02 +0000
Subject: [PATCH] Tweak GC check, make sure GC_init() is called even when ObjC
 code isn't using GC (stuff internal to the runtime may be)

---
 abi_version.c | 2 +-
 gc_boehm.c    | 4 ++--
 gc_ops.h      | 2 +-
 loader.c      | 6 ++++++
 properties.m  | 4 ++--
 5 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/abi_version.c b/abi_version.c
index 5321d57..5c3931f 100644
--- a/abi_version.c
+++ b/abi_version.c
@@ -61,7 +61,7 @@ static int known_abi_count =
 	}\
 } while(0)
 
-PRIVATE enum objc_gc_mode current_gc_mode = GC_Optional;
+static enum objc_gc_mode current_gc_mode = GC_Optional;
 
 static BOOL endsWith(const char *string, const char *suffix)
 {
diff --git a/gc_boehm.c b/gc_boehm.c
index 7ce2938..a74629d 100644
--- a/gc_boehm.c
+++ b/gc_boehm.c
@@ -511,7 +511,6 @@ static void runFinalizers(void)
 
 static void init(void)
 {
-	GC_INIT();
 	char *sigNumber;
 	// Dump GC stats on exit - uncomment when debugging.
 	if (getenv("LIBOBJC_DUMP_GC_STATUS_ON_EXIT"))
@@ -532,7 +531,7 @@ static void init(void)
 
 BOOL objc_collecting_enabled(void)
 {
-	return current_gc_mode != GC_None;
+	return isGCEnabled;
 }
 
 void objc_startCollectorThread(void)
@@ -580,6 +579,7 @@ PRIVATE struct gc_ops gc_ops_boehm =
 
 PRIVATE void enableGC(BOOL exclude)
 {
+	isGCEnabled = YES;
 	if (__sync_bool_compare_and_swap(&gc, &gc_ops_none, &gc_ops_boehm))
 	{
 		gc->init();
diff --git a/gc_ops.h b/gc_ops.h
index 9cda3f0..54045c0 100644
--- a/gc_ops.h
+++ b/gc_ops.h
@@ -54,7 +54,7 @@ enum objc_gc_mode
 /**
  * The current Objective-C garbage collection mode.
  */
-extern enum objc_gc_mode current_gc_mode;
+extern BOOL isGCEnabled;
 
 /**
  * The current set of garbage collector operations to use.
diff --git a/loader.c b/loader.c
index 6f3594f..d4c1552 100644
--- a/loader.c
+++ b/loader.c
@@ -4,6 +4,9 @@
 #include "lock.h"
 #include "loader.h"
 #include "visibility.h"
+#ifdef ENABLE_GC
+#include <gc/gc.h>
+#endif
 
 /**
  * Runtime lock.  This is exposed in 
@@ -32,6 +35,9 @@ void __objc_exec_class(struct objc_module_abi_8 *module)
 
 	if (first_run)
 	{
+#if ENABLE_GC
+		GC_INIT();
+#endif
 		// Create the main runtime lock.  This is not safe in theory, but in
 		// practice the first time that this function is called will be in the
 		// loader, from the main thread.  Future loaders may run concurrently,
diff --git a/properties.m b/properties.m
index 3e432a8..e205877 100644
--- a/properties.m
+++ b/properties.m
@@ -20,7 +20,7 @@ id objc_getProperty(id obj, SEL _cmd, ptrdiff_t offset, BOOL isAtomic)
 	if (nil == obj) { return nil; }
 	char *addr = (char*)obj;
 	addr += offset;
-	if (current_gc_mode == GC_Required)
+	if (isGCEnabled)
 	{
 		return *(id*)addr;
 	}
@@ -47,7 +47,7 @@ void objc_setProperty(id obj, SEL _cmd, ptrdiff_t offset, id arg, BOOL isAtomic,
 	char *addr = (char*)obj;
 	addr += offset;
 
-	if (current_gc_mode == GC_Required)
+	if (isGCEnabled)
 	{
 		if (isCopy)
 		{