gcc-6.2: backport fix of check for empty string in ubsan.c

Building gcc-cross-initial with GCC7 on the host fails due to the
comparison of a pointer to an integer in ubsan_use_new_style_p, which
is forbidden by ISO C++:

ubsan.c:1474:23: error: ISO C++ forbids comparison between pointer and
integer [-fpermissive]
       || xloc.file == '\0' || xloc.file[0] == '\xff'

Backport the fix from upstream GCC to enable the build with GCC 7

(From OE-Core rev: 7a7fcbab0365b9501c737dbc02715be14dda72a3)

(From OE-Core rev: ad685600d52b2e8b6f4cdbf46baa9f14b51565dd)

Signed-off-by: Joshua Lock <joshua.g.lock@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 31 insertions, 2 deletions

diff --git a/meta/recipes-devtools/gcc/gcc-6.2.inc b/meta/recipes-devtools/gcc/gcc-6.2.inc
index b118995e1d..39ae653805 100644
--- a/meta/recipes-devtools/gcc/gcc-6.2.inc
+++ b/meta/recipes-devtools/gcc/gcc-6.2.inc
@@ -80,8 +80,9 @@ SRC_URI = "\
            file://0047-libgcc_s-Use-alias-for-__cpu_indicator_init-instead-.patch \
            ${BACKPORTS} \
 "
-BACKPORTS = ""
-
+BACKPORTS = "\
+           file://ubsan-fix-check-empty-string.patch \
+"
 SRC_URI[md5sum] = "9768625159663b300ae4de2f4745fcc4"
 SRC_URI[sha256sum] = "9944589fc722d3e66308c0ce5257788ebd7872982a718aa2516123940671b7c5"
 
diff --git a/meta/recipes-devtools/gcc/gcc-6.2/ubsan-fix-check-empty-string.patch b/meta/recipes-devtools/gcc/gcc-6.2/ubsan-fix-check-empty-string.patch
new file mode 100644
index 0000000000..c0127198e0
--- /dev/null
+++ b/meta/recipes-devtools/gcc/gcc-6.2/ubsan-fix-check-empty-string.patch
@@ -0,0 +1,28 @@
+From 8db2cf6353c13f2a84cbe49b689654897906c499 Mon Sep 17 00:00:00 2001
+From: kyukhin <kyukhin@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date: Sat, 3 Sep 2016 10:57:05 +0000
+Subject: [PATCH] gcc/   * ubsan.c (ubsan_use_new_style_p): Fix check for empty
+ string.
+
+git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@239971 138bc75d-0d04-0410-961f-82ee72b054a4
+
+Upstream-Status: Backport
+Signed-off-by: Joshua Lock <joshua.g.lock@intel.com>
+
+---
+ gcc/ubsan.c   | 2 +-
+ 2 files changed, 5 insertions(+), 1 deletion(-)
+
+Index: gcc-6.3.0/gcc/ubsan.c
+===================================================================
+--- gcc-6.3.0.orig/gcc/ubsan.c
++++ gcc-6.3.0/gcc/ubsan.c
+@@ -1471,7 +1471,7 @@ ubsan_use_new_style_p (location_t loc)
+ 
+   expanded_location xloc = expand_location (loc);
+   if (xloc.file == NULL || strncmp (xloc.file, "\1", 2) == 0
+-      || xloc.file == '\0' || xloc.file[0] == '\xff'
++      || xloc.file[0] == '\0' || xloc.file[0] == '\xff'
+       || xloc.file[1] == '\xff')
+     return false;
+