From: Ivan Maidanski <ivmai@mail.ru>
Date: Fri, 1 Jul 2016 07:41:16 +0000 (+0300)
Subject: Fix 'arg parameter might be clobbered by setjmp' compiler warning
X-Git-Tag: v7.4.6~268
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8c87595187e33458cf1d0a9b343cab32e0577301;p=gc

Fix 'arg parameter might be clobbered by setjmp' compiler warning
(Apply squashed commit of 8ffc3db and 65b50c0 from 'master' branch.)

* mach_dep.c (GC_with_callee_saves_pushed): Make "arg" parameter
volatile (to prevent it from potential clobbering).
* include/private/gc_priv.h (GC_with_callee_saves_pushed): Add
volatile for arg (to match the function definition).
---

diff --git a/include/private/gc_priv.h b/include/private/gc_priv.h
index 380bbf3a..59f88112 100644
--- a/include/private/gc_priv.h
+++ b/include/private/gc_priv.h
@@ -1611,7 +1611,7 @@ GC_EXTERN void (*GC_push_typed_structures)(void);
                         /* the typed allocation support if unused.      */
 
 GC_INNER void GC_with_callee_saves_pushed(void (*fn)(ptr_t, void *),
-                                          ptr_t arg);
+                                          volatile ptr_t arg);
 
 #if defined(SPARC) || defined(IA64)
   /* Cause all stacked registers to be saved in memory.  Return a       */
diff --git a/mach_dep.c b/mach_dep.c
index 9c95e698..038fa85e 100644
--- a/mach_dep.c
+++ b/mach_dep.c
@@ -211,7 +211,7 @@
 /* are somewhere on the stack, and then call fn(arg, ctxt).             */
 /* ctxt is either a pointer to a ucontext_t we generated, or NULL.      */
 GC_INNER void GC_with_callee_saves_pushed(void (*fn)(ptr_t, void *),
-                                          ptr_t arg)
+                                          volatile ptr_t arg)
 {
     volatile int dummy;
     void * context = 0;