From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 21 Dec 2016 17:52:28 +0000 (-0800)
Subject: Port dumping better to WSL
X-Git-Tag: emacs-26.0.90~1041
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=cf6ce9a1fe320ebe5b238af5f7af9416ac954855;p=emacs.git

Port dumping better to WSL

Problem reported by Angelo Graziosi in:
http://lists.gnu.org/archive/html/emacs-devel/2016-12/msg00822.html
* src/sysdep.c (disable_address_randomization):
Detect buggy platforms where 'personality' always returns 0.
---

diff --git a/src/sysdep.c b/src/sysdep.c
index 96c9e538409..86d420f66c4 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -144,11 +144,16 @@ static const int baud_convert[] =
 bool
 disable_address_randomization (void)
 {
-  bool disabled = false;
   int pers = personality (0xffffffff);
-  disabled = (! (pers & ADDR_NO_RANDOMIZE)
-	      && 0 <= personality (pers | ADDR_NO_RANDOMIZE));
-  return disabled;
+  if (pers < 0)
+    return false;
+  int desired_pers = pers | ADDR_NO_RANDOMIZE;
+
+  /* Call 'personality' twice, to detect buggy platforms like WSL
+     where 'personality' always returns 0.  */
+  return (pers != desired_pers
+	  && personality (desired_pers) == pers
+	  && personality (0xffffffff) == desired_pers);
 }
 #endif