From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 6 May 2017 21:21:19 +0000 (-0700)
Subject: Pacify GCC setjmp/longjmp warning
X-Git-Tag: emacs-26.0.90~521^2~448
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=0a13c725132ade2709da217cac70e3847a387c58;p=emacs.git

Pacify GCC setjmp/longjmp warning

* src/eval.c (internal_lisp_condition_case): Do not modify local
var VAR, to pacify GCC’s setjmp/longjmp warning which in some
cases mistakenly diagnoses VAR possibly being modified between a
setjmp and a longjmp.
---

diff --git a/src/eval.c b/src/eval.c
index 0030271c533..848955c2794 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1277,18 +1277,19 @@ internal_lisp_condition_case (Lisp_Object var, Lisp_Object bodyform,
 	  if (NILP (var))
 	    return Fprogn (handler_body);
 
+	  Lisp_Object handler_var = var;
 	  if (!NILP (Vinternal_interpreter_environment))
 	    {
 	      val = Fcons (Fcons (var, val),
 			   Vinternal_interpreter_environment);
-	      var = Qinternal_interpreter_environment;
+	      handler_var = Qinternal_interpreter_environment;
 	    }
 
-	  /* Bind VAR to VAL while evaluating HANDLER_BODY.  The
-	     unbind_to just undoes VAR's binding; whoever longjumped
+	  /* Bind HANDLER_VAR to VAL while evaluating HANDLER_BODY.
+	     The unbind_to undoes just this binding; whoever longjumped
 	     to us unwound the stack to C->pdlcount before throwing.  */
 	  ptrdiff_t count = SPECPDL_INDEX ();
-	  specbind (var, val);
+	  specbind (handler_var, val);
 	  return unbind_to (count, Fprogn (handler_body));
 	}
     }