m4: Fix build with clang especially on armv7

Signed-off-by: Khem Raj <raj.khem@gmail.com>

3 files changed, 22 insertions, 1 deletions

diff --git a/conf/nonclangable.conf b/conf/nonclangable.conf
index d09b212..b4f8ca8 100644
--- a/conf/nonclangable.conf
+++ b/conf/nonclangable.conf
@@ -41,7 +41,6 @@ TOOLCHAIN_pn-libvorbis = "gcc"
 #        DO_NEXT_OP(len);
 TOOLCHAIN_pn-mozjs = "gcc"
 
-TOOLCHAIN_pn-m4 = "gcc"
 TOOLCHAIN_pn-mtools = "gcc"
 TOOLCHAIN_pn-openssl = "gcc"
 TOOLCHAIN_pn-openjdk-8 = "gcc"
diff --git a/recipes-devtools/m4/m4/disable_builtin_mul_overflow.patch b/recipes-devtools/m4/m4/disable_builtin_mul_overflow.patch
new file mode 100644
index 0000000..1fe1beb
--- /dev/null
+++ b/recipes-devtools/m4/m4/disable_builtin_mul_overflow.patch
@@ -0,0 +1,19 @@
+clang/arm has this issue where it generates call to __mulodi4
+which is only in compiler-rt and we end with errors
+
+/usr/src/debug/m4/1.4.18-r0/build/src/../../m4-1.4.18/lib/xalloc.h:107: undefined reference to `__mulodi4'
+
+
+Index: m4-1.4.18/lib/xalloc-oversized.h
+===================================================================
+--- m4-1.4.18.orig/lib/xalloc-oversized.h
++++ m4-1.4.18/lib/xalloc-oversized.h
+@@ -52,7 +52,7 @@ typedef size_t __xalloc_count_type;
+ #elif ((5 <= __GNUC__ \
+         || (__has_builtin (__builtin_mul_overflow) \
+             && __has_builtin (__builtin_constant_p))) \
+-       && !__STRICT_ANSI__)
++       && !__STRICT_ANSI__ && !__clang__)
+ # define xalloc_oversized(n, s) \
+    (__builtin_constant_p (n) && __builtin_constant_p (s) \
+     ? __xalloc_oversized (n, s) \
diff --git a/recipes-devtools/m4/m4_%.bbappend b/recipes-devtools/m4/m4_%.bbappend
new file mode 100644
index 0000000..e00f7c4
--- /dev/null
+++ b/recipes-devtools/m4/m4_%.bbappend
@@ -0,0 +1,3 @@
+FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"
+
+SRC_URI += "file://disable_builtin_mul_overflow.patch"