PR go/60406

runtime: Check callers in can_recover if return address	doesn't match.

Also use __builtin_extract_return_address and tighten up the
checks in FFI code.

Fixes PR 60406.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@216003 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 10 insertions, 17 deletions

diff --git a/libgo/go/reflect/makefunc_ffi_c.c b/libgo/go/reflect/makefunc_ffi_c.c
index fba269dcb58..a3dfd4acd2c 100644
--- a/libgo/go/reflect/makefunc_ffi_c.c
+++ b/libgo/go/reflect/makefunc_ffi_c.c
@@ -36,21 +36,23 @@ void ffiFree(void *data)
    Go callback function (passed in user_data) with the pointer to the
    arguments and the results area.  */
 
+static void ffi_callback (ffi_cif *, void *, void **, void *)
+  __asm__ ("reflect.ffi_callback");
+
 static void
 ffi_callback (ffi_cif* cif __attribute__ ((unused)), void *results,
 	      void **args, void *user_data)
 {
-  Location locs[6];
+  Location locs[8];
   int n;
   int i;
-  const void *pc;
   FuncVal *fv;
   void (*f) (void *, void *);
 
   /* This function is called from some series of FFI closure functions
-     called by a Go function.  We want to pass the PC of the Go
-     function to makefunc_can_recover.  Look up the stack for a
-     function that is definitely not an FFI function.  */
+     called by a Go function.  We want to see whether the caller of
+     the closure functions can recover.  Look up the stack and skip
+     the FFI functions.  */
   n = runtime_callers (1, &locs[0], sizeof locs / sizeof locs[0], true);
   for (i = 0; i < n; i++)
     {
@@ -61,28 +63,19 @@ ffi_callback (ffi_cif* cif __attribute__ ((unused)), void *results,
       if (locs[i].function.len < 4)
 	break;
       name = locs[i].function.str;
-      if (*name == '_')
-	{
-	  if (locs[i].function.len < 5)
-	    break;
-	  ++name;
-	}
       if (name[0] != 'f' || name[1] != 'f' || name[2] != 'i' || name[3] != '_')
 	break;
     }
   if (i < n)
-    pc = (const void *) locs[i].pc;
-  else
-    pc = __builtin_return_address (0);
-
-  __go_makefunc_can_recover (pc);
+    __go_makefunc_ffi_can_recover (locs + i, n - i);
 
   fv = (FuncVal *) user_data;
   __go_set_closure (fv);
   f = (void *) fv->fn;
   f (args, results);
 
-  __go_makefunc_returning ();
+  if (i < n)
+    __go_makefunc_returning ();
 }
 
 /* Allocate an FFI closure and arrange to call ffi_callback.  */