[OE-core] [RFC][PATCH] gcc-runtime.inc: force libstdc++ to always use gcc4 compatible ABI

[Andre McCurdy]

Experimental hack, not expected to be merged.

Without this, the http://www.cplusplus.com/reference/string/string/append/
example fails to build with -std=c++11 and it's not clear why (it's as if we
build a version of libstdc++ which supports only the old ABI but with headers
which try to use the new ABI when compiled with -std=c++11 ?). As a workaround,
force libstdc++ to provide, and default to using, the old ABI in all cases.

See also:

  https://gcc.gnu.org/onlinedocs/libstdc++/manual/configure.html
  https://mail.gnome.org/archives/gtkmm-list/2015-June/msg00026.html
  https://wiki.debian.org/GCC5

Signed-off-by: Andre McCurdy <armccurdy at gmail.com>
---
 meta/recipes-devtools/gcc/gcc-runtime.inc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/meta/recipes-devtools/gcc/gcc-runtime.inc b/meta/recipes-devtools/gcc/gcc-runtime.inc
index f20d298..3a476cd 100644
--- a/meta/recipes-devtools/gcc/gcc-runtime.inc
+++ b/meta/recipes-devtools/gcc/gcc-runtime.inc
@@ -10,6 +10,19 @@ EXTRA_OECONF_PATHS = "\
 
 EXTRA_OECONF_append_linuxstdbase = " --enable-clocale=gnu"
 
+# gcc-runtime.inc: force libstdc++ to always use gcc4 compatible ABI
+# Experimental hack. Without this, the http://www.cplusplus.com/reference/string/string/append/
+# example fails to build with -std=c++11 and it's not clear why (it's as if we
+# build a version of libstdc++ which supports only the old ABI but with headers
+# which try to use the new ABI when compiled with -std=c++11 ?). As a workaround,
+# force libstdc++ to provide, and default to using, the old ABI in all cases.
+# See also:
+# https://gcc.gnu.org/onlinedocs/libstdc++/manual/configure.html
+# https://mail.gnome.org/archives/gtkmm-list/2015-June/msg00026.html
+# https://wiki.debian.org/GCC5
+#
+EXTRA_OECONF_append = " --disable-libstdcxx-dual-abi --with-default-libstdcxx-abi=gcc4-compatible"
+
 RUNTIMETARGET = "libssp libstdc++-v3 libgomp libatomic \
     ${@bb.utils.contains_any('FORTRAN', [',fortran',',f77'], 'libquadmath', '', d)} \
 "
-- 
1.9.1