diffutils: Fix build on ppc/musl

Backport a patch from libsigsegv

(From OE-Core rev: 2115602f898f915c8e20358b5523da10d3b611f3)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-extended/diffutils/diffutils/0001-mcontext-is-not-a-standard-layout-so-glibc-and-musl-.patch

@@ -0,0 +1,33 @@
+From f385ad6639380eb6dfa8b8eb4a5ba65dd12db744 Mon Sep 17 00:00:00 2001
+From: Khem Raj <raj.khem@gmail.com>
+Date: Fri, 25 Mar 2022 13:43:19 -0700
+Subject: [PATCH] mcontext is not a standard layout so glibc and musl differ
+
+This is already applied to libsigsegv upstream, hopefully next version
+of grep will update its internal copy and we can drop this patch
+
+Upstream-Status: Backport [https://git.savannah.gnu.org/gitweb/?p=libsigsegv.git;a=commitdiff;h=a6ff69873110c0a8ba6f7fd90532dbc11224828c]
+
+Signed-off-by: Khem Raj <raj.khem@gmail.com>
+---
+ lib/sigsegv.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/lib/sigsegv.c b/lib/sigsegv.c
+index 998c827..b6f4841 100644
+--- a/lib/sigsegv.c
++++ b/lib/sigsegv.c
+@@ -219,8 +219,8 @@ int libsigsegv_version = LIBSIGSEGV_VERSION;
+ #   define SIGSEGV_FAULT_STACKPOINTER  ((ucontext_t *) ucp)->uc_mcontext.gp_regs[1]
+ #  else /* 32-bit */
+ /* both should be equivalent */
+-#   if 0
+-#    define SIGSEGV_FAULT_STACKPOINTER  ((ucontext_t *) ucp)->uc_mcontext.regs->gpr[1]
++#   if ! defined __GLIBC__
++#    define SIGSEGV_FAULT_STACKPOINTER  ((ucontext_t *) ucp)->uc_regs->gregs[1]
+ #   else
+ #    define SIGSEGV_FAULT_STACKPOINTER  ((ucontext_t *) ucp)->uc_mcontext.uc_regs->gregs[1]
+ #   endif
+-- 
+2.35.1
+

meta/recipes-extended/diffutils/diffutils_3.8.bb

@@ -6,6 +6,7 @@ require diffutils.inc
 SRC_URI = "${GNU_MIRROR}/diffutils/diffutils-${PV}.tar.xz \
            file://run-ptest \
            file://0001-Skip-strip-trailing-cr-test-case.patch \
+           file://0001-mcontext-is-not-a-standard-layout-so-glibc-and-musl-.patch \
            "
 
 SRC_URI[sha256sum] = "a6bdd7d1b31266d11c4f4de6c1b748d4607ab0231af5188fc2533d0ae2438fec"