diff --git a/src/pkg/runtime/darwin/amd64/signal.c b/src/pkg/runtime/darwin/amd64/signal.c
index 648ef207ca6..5dc811cfa7f 100644
--- a/src/pkg/runtime/darwin/amd64/signal.c
+++ b/src/pkg/runtime/darwin/amd64/signal.c
@@ -112,8 +112,8 @@ sighandler(int32 sig, Siginfo *info, void *context)
 	printf("\n");
 
 	if(gotraceback()){
-		traceback((void*)r->rip, (void*)r->rsp, 0, (void*)r->r15);
-		tracebackothers((void*)r->r15);
+		traceback((void*)r->rip, (void*)r->rsp, 0, g);
+		tracebackothers(g);
 		dumpregs(r);
 	}
 
diff --git a/src/pkg/runtime/freebsd/amd64/signal.c b/src/pkg/runtime/freebsd/amd64/signal.c
index 57bfcfb55eb..09053ac7868 100644
--- a/src/pkg/runtime/freebsd/amd64/signal.c
+++ b/src/pkg/runtime/freebsd/amd64/signal.c
@@ -106,8 +106,8 @@ sighandler(int32 sig, Siginfo* info, void* context)
 	printf("\n");
 
 	if(gotraceback()){
-		traceback((void*)r->mc_rip, (void*)r->mc_rsp, 0, (void*)r->mc_r15);
-		tracebackothers((void*)r->mc_r15);
+		traceback((void*)r->mc_rip, (void*)r->mc_rsp, 0, g);
+		tracebackothers(g);
 		dumpregs(r);
 	}
 
diff --git a/src/pkg/runtime/linux/amd64/signal.c b/src/pkg/runtime/linux/amd64/signal.c
index 63c3a2e6ea5..e46a0944c57 100644
--- a/src/pkg/runtime/linux/amd64/signal.c
+++ b/src/pkg/runtime/linux/amd64/signal.c
@@ -105,8 +105,8 @@ sighandler(int32 sig, Siginfo* info, void* context)
 	printf("\n");
 
 	if(gotraceback()){
-		traceback((void*)r->rip, (void*)r->rsp, 0, (void*)r->r15);
-		tracebackothers((void*)r->r15);
+		traceback((void*)r->rip, (void*)r->rsp, 0, g);
+		tracebackothers(g);
 		dumpregs(r);
 	}