Makefile: Manually forward RELAX_FLAG to the assembler when linking with LLD

When generating code with -mno-relax, GCC puts .option norelax in
the generated assembly, and so doesn’t bother passing on -mno-relax
to the assembler. This has the unfortunate effect that, when using
GCC to assemble hand-written assembly, -mno-relax does nothing,
and we have to pass -Wa,-mno-relax to manually forward it to the
assembler.

This is an old GCC bug that was fixed [1] recently. For the time
being, let's pass "-Wa,-mno-relax" to ASFLAGS for the GCC + LLD
combination to work, e.g.:

  $ make CC=riscv64-unknown-elf-gcc LLVM=1 PLATFORM=generic

[1] https://github.com/gcc-mirror/gcc/commit/3b0a7d624e64eeb81e4d5e8c62c46d86ef521857

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

diff --git a/Makefile b/Makefile
index 129b8ed..16d9dca 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -272,6 +272,11 @@ ASFLAGS            +=      -mno-save-restore -mstrict-align
 ASFLAGS                +=      -mabi=$(PLATFORM_RISCV_ABI) -march=$(PLATFORM_RISCV_ISA)
 ASFLAGS                +=      -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
 ASFLAGS                +=      $(RELAX_FLAG)
+ifneq ($(CC_IS_CLANG),y)
+ifneq ($(RELAX_FLAG),)
+ASFLAGS                +=      -Wa,$(RELAX_FLAG)
+endif
+endif
 ASFLAGS                +=      $(GENFLAGS)
 ASFLAGS                +=      $(platform-asflags-y)
 ASFLAGS                +=      $(firmware-asflags-y)