From: trippels <trippels@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 4 Mar 2015 17:28:56 +0000 (+0000)
Subject: Fix PR65261
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=45e87ca9abf8edb4e36ab704e9fdae03ea2fe94c;p=thirdparty%2Fgcc.git

Fix PR65261

Running bootstrap-ubsan on ppc64le shows many instances of:

  libcpp/lex.c:552:30: runtime error: load of misaligned address
  0x01001f31d37a for type 'const uchar', which requires 16 byte alignment

But the unaligned vector loads are intended in this case, because they
are preferable to forced-alignment on POWER8. So just silence the ubsan
errors.

2015-03-02  Markus Trippelsdorf  <markus@trippelsdorf.de>

include/
	PR target/65261
	* ansidecl.h (ATTRIBUTE_NO_SANITIZE_UNDEFINED): New macro.

libcpp/
	PR target/65261
	* lex.c (search_line_fast): Silence ubsan errors.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@221190 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/include/ChangeLog b/include/ChangeLog
index 689873b26b3b..bd072ae59b4d 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-02  Markus Trippelsdorf  <markus@trippelsdorf.de>
+
+	PR target/65261
+	* ansidecl.h (ATTRIBUTE_NO_SANITIZE_UNDEFINED): New macro.
+
 2015-02-19  Pedro Alves  <palves@redhat.com>
 
 	* floatformat.h [__cplusplus]: Wrap in extern "C".
diff --git a/include/ansidecl.h b/include/ansidecl.h
index 0fb23bba792d..04d75c33f747 100644
--- a/include/ansidecl.h
+++ b/include/ansidecl.h
@@ -276,6 +276,15 @@ So instead we use the macro below and test it against specific values.  */
 # endif /* GNUC >= 4.3 */
 #endif /* ATTRIBUTE_HOT */
 
+/* Attribute 'no_sanitize_undefined' was valid as of gcc 4.9.  */
+#ifndef ATTRIBUTE_NO_SANITIZE_UNDEFINED
+# if (GCC_VERSION >= 4009)
+#  define ATTRIBUTE_NO_SANITIZE_UNDEFINED __attribute__ ((no_sanitize_undefined))
+# else
+#  define ATTRIBUTE_NO_SANITIZE_UNDEFINED
+# endif /* GNUC >= 4.9 */
+#endif /* ATTRIBUTE_NO_SANITIZE_UNDEFINED */
+
 /* We use __extension__ in some places to suppress -pedantic warnings
    about GCC extensions.  This feature didn't work properly before
    gcc 2.8.  */
diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog
index 325f70609633..2d84835b7b72 100644
--- a/libcpp/ChangeLog
+++ b/libcpp/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-02  Markus Trippelsdorf  <markus@trippelsdorf.de>
+
+	PR target/65261
+	* lex.c (search_line_fast): Silence ubsan errors.
+
 2015-02-03    <dodji@redhat.com>
 
 	PR preprocessor/64803
diff --git a/libcpp/lex.c b/libcpp/lex.c
index 4638510166fa..0dc473711833 100644
--- a/libcpp/lex.c
+++ b/libcpp/lex.c
@@ -519,6 +519,7 @@ init_vectorized_lexer (void)
    and VSX unaligned loads (when VSX is available).  This is otherwise
    the same as the pre-GCC 5 version.  */
 
+ATTRIBUTE_NO_SANITIZE_UNDEFINED
 static const uchar *
 search_line_fast (const uchar *s, const uchar *end ATTRIBUTE_UNUSED)
 {