[PATCH] Forbid section anchors for ASan build (PR sanitizer/81697)

[Slava Barinov]

       gcc/
       * varasm.c (use_object_blocks_p): Forbid section anchors for ASan

       gcc/testsuite/
       * g++.dg/asan/global-alignment.cc: New test to test global
       variables alignment.

Signed-off-by: Slava Barinov <v.bari...@samsung.com>
---
 gcc/ChangeLog                                 |  6 ++++++
 gcc/testsuite/ChangeLog                       |  3 +++
 gcc/testsuite/g++.dg/asan/global-alignment.cc | 17 +++++++++++++++++
 gcc/varasm.c                                  |  3 ++-
 4 files changed, 28 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/asan/global-alignment.cc

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index dde91ceea5b..d840825e7c8 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2017-08-08  Vyacheslav Barinov  <v.bari...@samsung.com>
+
+       PR sanitizer/81697
+       * varasm.c (use_object_blocks_p): Forbid section anchors for ASan
+       build.
+
 2017-08-08  Martin Liska  <mli...@suse.cz>
 
        * asan.c: Include header files.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 315af8361df..0a0a5850c74 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2017-08-08  Vyacheslav Barinov  <v.bari...@samsung.com>
 
+       PR sanitizer/81697
+       * g++.dg/asan/global-alignment.cc: New test to test global
+       variables alignment.
        * g++.dg/asan/asan.exp: Switch on *.cc tests.
 
 2017-08-07  Michael Meissner  <meiss...@linux.vnet.ibm.com>
diff --git a/gcc/testsuite/g++.dg/asan/global-alignment.cc 
b/gcc/testsuite/g++.dg/asan/global-alignment.cc
new file mode 100644
index 00000000000..c011c703ea6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/asan/global-alignment.cc
@@ -0,0 +1,17 @@
+/* { dg-options "-fmerge-all-constants" } */
+/* { dg-do compile } */
+/* { dg-skip-if "" { *-*-* } { "-O0" } { "" } } */
+
+#include <string>
+#include <map>
+
+const char kRecoveryInstallString[] = "NEW";
+const char kRecoveryUpdateString[] = "UPDATE";
+const char kRecoveryUninstallationString[] = "UNINSTALL";
+
+const std::map<std::string, int> kStringToRequestMap = {
+  {kRecoveryInstallString, 0},
+  {kRecoveryUpdateString, 0},
+  {kRecoveryUninstallationString, 0},
+};
+/* { dg-final { scan-assembler-times 
{\.section\s+\.rodata\n(?:(?!\.section).)*\.(string|ascii|asciz)\s+"NEW} 1 } } 
*/
diff --git a/gcc/varasm.c b/gcc/varasm.c
index e0834a1ff3b..dbeb8d9331e 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -346,7 +346,8 @@ get_section (const char *name, unsigned int flags, tree 
decl)
 static bool
 use_object_blocks_p (void)
 {
-  return flag_section_anchors;
+  return (flag_section_anchors
+         && !(flag_sanitize & SANITIZE_ADDRESS));
 }
 
 /* Return the object_block structure for section SECT.  Create a new
-- 
2.13.3