From c3b53559965a4c6f48274c3cbcb43eb6ef23ae14 Mon Sep 17 00:00:00 2001
From: Philipp Stephani <phst@google.com>
Date: Sat, 1 Aug 2020 14:13:55 +0200
Subject: [PATCH] Suppress leak detector in some cases

We intentionally leak some objects.  Prevent the ASan leak detector
from raising false alarms in these cases.

* configure.ac: Search for lsan_interface.h header.

* src/data.c (make_blv): Allow leaking of buffer-local values.

* src/buffer.c (enlarge_buffer_text): Allow leaking of buffer text.

* src/emacs-module.c (Fmodule_load, initialize_environment): Allow
intentional leak of runtime and environment objects if module
assertions are enabled.
---
 configure.ac       |  3 ++-
 src/buffer.c       |  7 +++++++
 src/data.c         |  7 +++++++
 src/emacs-module.c | 18 +++++++++++++++++-
 4 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 148c50e0b39..b4674e3204b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1740,7 +1740,8 @@ AC_CHECK_HEADERS_ONCE(
   sys/sysinfo.h
   coff.h pty.h
   sys/resource.h
-  sys/utsname.h pwd.h utmp.h util.h)
+  sys/utsname.h pwd.h utmp.h util.h
+  sanitizer/lsan_interface.h)
 
 AC_CACHE_CHECK([for ADDR_NO_RANDOMIZE],
   [emacs_cv_personality_addr_no_randomize],
diff --git a/src/buffer.c b/src/buffer.c
index f1cb4d50414..3456a46be3e 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -28,6 +28,10 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include <stdlib.h>
 #include <unistd.h>
 
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+#include <sanitizer/lsan_interface.h>
+#endif
+
 #include <verify.h>
 
 #include "lisp.h"
@@ -5083,6 +5087,9 @@ enlarge_buffer_text (struct buffer *b, ptrdiff_t delta)
 #else
   p = xrealloc (b->text->beg, new_nbytes);
 #endif
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+  __lsan_ignore_object (p);
+#endif
 
   if (p == NULL)
     {
diff --git a/src/data.c b/src/data.c
index 1db0a983b49..c261e8e90dd 100644
--- a/src/data.c
+++ b/src/data.c
@@ -23,6 +23,10 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include <math.h>
 #include <stdio.h>
 
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+#include <sanitizer/lsan_interface.h>
+#endif
+
 #include <byteswap.h>
 #include <count-one-bits.h>
 #include <count-trailing-zeros.h>
@@ -1784,6 +1788,9 @@ make_blv (struct Lisp_Symbol *sym, bool forwarded,
   set_blv_defcell (blv, tem);
   set_blv_valcell (blv, tem);
   set_blv_found (blv, false);
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+  __lsan_ignore_object (blv);
+#endif
   return blv;
 }
 
diff --git a/src/emacs-module.c b/src/emacs-module.c
index ac9ac824b7b..8d06a24210b 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -84,6 +84,10 @@ To add a new module function, proceed as follows:
 #include <stdlib.h>
 #include <time.h>
 
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+#include <sanitizer/lsan_interface.h>
+#endif
+
 #include "lisp.h"
 #include "bignum.h"
 #include "dynlib.h"
@@ -1095,7 +1099,16 @@ DEFUN ("module-load", Fmodule_load, Smodule_load, 1, 1, 0,
      for two different runtime objects are guaranteed to be distinct,
      which we can use for checking the liveness of runtime
      pointers.  */
-  struct emacs_runtime *rt = module_assertions ? xmalloc (sizeof *rt) : &rt_pub;
+  struct emacs_runtime *rt;
+  if (module_assertions)
+    {
+      rt = xmalloc (sizeof *rt);
+#ifdef HAVE_SANITIZER_LSAN_INTERFACE_H
+      __lsan_ignore_object (rt);
+#endif
+    }
+  else
+    rt = &rt_pub;
   rt->size = sizeof *rt;
   rt->private_members = &rt_priv;
   rt->get_environment = module_get_environment;
@@ -1411,7 +1424,10 @@ static emacs_env *
 initialize_environment (emacs_env *env, struct emacs_env_private *priv)
 {
   if (module_assertions)
+    {
       env = xmalloc (sizeof *env);
+      __lsan_ignore_object (env);
+    }
 
   priv->pending_non_local_exit = emacs_funcall_exit_return;
   initialize_storage (&priv->storage);
-- 
2.39.2