[oe] [PATCH] mozjs: disable null pointer optimization with GCC >= 6

[Ricardo Salveti]

Mozjs fails to start on several architectures due broken build
optimizations when built with GCC >= 6.

Set -fno-tree-vrp -fno-strict-aliasing -fno-delete-null-pointer-checks
to both CFLAGS and CXXFLAGS as workaround (flags also used by Firefox
and Fedora).

Signed-off-by: Ricardo Salveti <ricardo at foundries.io>
---
 meta-oe/recipes-extended/mozjs/mozjs_52.8.1.bb | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/meta-oe/recipes-extended/mozjs/mozjs_52.8.1.bb b/meta-oe/recipes-extended/mozjs/mozjs_52.8.1.bb
index fe9698f..626522e 100644
--- a/meta-oe/recipes-extended/mozjs/mozjs_52.8.1.bb
+++ b/meta-oe/recipes-extended/mozjs/mozjs_52.8.1.bb
@@ -32,6 +32,11 @@ CONFLICT_DISTRO_FEATURES_mipsarchn32 = "ld-is-gold"
 
 DEPENDS += "nspr zlib"
 
+# Disable null pointer optimization in gcc >= 6
+# https://bugzilla.redhat.com/show_bug.cgi?id=1328045
+CFLAGS += "-fno-tree-vrp -fno-strict-aliasing -fno-delete-null-pointer-checks"
+CXXFLAGS += "-fno-tree-vrp -fno-strict-aliasing -fno-delete-null-pointer-checks"
+
 # nspr's package-config is ignored so set libs manually
 EXTRA_OECONF = " \
     --target=${TARGET_SYS} \
-- 
2.7.4