[Buildroot] [git commit] package/gmp: fix compile error for riscv

[Thomas Petazzoni]

commit: https://git.buildroot.net/buildroot/commit/?id=97c06c5b593a05716a3bd8941d2e208fa592cb38
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/master

In commit 87b2a30319394c2cc79efae1af7833cad8c62b32 gmp got updated
to 6.2.1, since then the compile error exist.

Compile error looks like this:
tmp-mul_1.s: Assembler messages:
tmp-mul_1.s:55: Error: unrecognized opcode `mul a5,a7,a3'
tmp-mul_1.s:57: Error: unrecognized opcode `mulhu a7,a7,a3'

Patch should be backported to stable branches.

Fixes:
 - http://autobuild.buildroot.net/results/2f2/2f2112bea73adbf49eabb62fe6cda6a9cd5d0567
 - http://autobuild.buildroot.net/results/566/566a4945555b781ed127997176f73b3c17ecab5d

Signed-off-by: Waldemar Brodkorb <wbx at openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
---
 package/gmp/gmp.mk | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/package/gmp/gmp.mk b/package/gmp/gmp.mk
index c52a5214a6..1a50b0bf69 100644
--- a/package/gmp/gmp.mk
+++ b/package/gmp/gmp.mk
@@ -20,6 +20,11 @@ ifeq ($(BR2_m68k_cf)$(BR2_MIPS_CPU_MIPS32R6)$(BR2_MIPS_CPU_MIPS64R6)$(BR2_ARM_CP
 GMP_CONF_OPTS += --disable-assembly
 endif
 
+# GMP needs M extension for riscv assembly
+ifeq ($(BR2_RISCV_ISA_RVM),)
+GMP_CONF_OPTS += --disable-assembly
+endif
+
 ifeq ($(BR2_INSTALL_LIBSTDCPP),y)
 GMP_CONF_OPTS += --enable-cxx
 else