With binutils snapshots since 29.07.2014 I get the following build failure:
{standard input}: Warning: .gnu_attribute 4,3 requires `softfloat'
LD arch/mips/alchemy/common/built-in.o
mipsel-softfloat-linux-gnu-ld: Warning: arch/mips/alchemy/common/built-in.o
uses -msoft-float (set by arch/mips/alchemy/common/prom.o),
arch/mips/alchemy/common/sleeper.o uses -mhard-float
Extend cflags with a soft-float directive for the assembler, and add
hardfloat directives to assembler files dealing with FPU
registers to compensate.
Signed-off-by: Manuel Lauss <manuel.lauss@xxxxxxxxx>
---
V2: cover more assembler files.
This was introduced in binutils commit 351cdf24d223290b15fa991e5052ec9e9bd1e284
("[MIPS] Implement O32 FPXX, FP64 and FP64A ABI extensions"), and it seems is only
a problem with my gcc 4.9 or a very recent snapshot of gcc-4.10.
With gcc-4.8, the source builds, with 4.9 it aborts after the above error,
with 4.10 (which apparently passes -msoft-float along to the assembler automatically)
the .hardfloat directives are required.
arch/mips/Makefile | 2 +-
arch/mips/kernel/r2300_switch.S | 1 +
arch/mips/kernel/r4k_fpu.S | 1 +
arch/mips/kernel/r4k_switch.S | 1 +
arch/mips/kernel/r6000_fpu.S | 1 +
5 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 9336509..cffbd49 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -88,7 +88,7 @@ all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlinuz
# crossformat linking we rely on the elf2ecoff tool for format conversion.
#
cflags-y += -G 0 -mno-abicalls -fno-pic -pipe
-cflags-y += -msoft-float
+cflags-y += -msoft-float -Wa,-msoft-float
LDFLAGS_vmlinux += -G 0 -static -n -nostdlib
KBUILD_AFLAGS_MODULE += -mlong-calls
KBUILD_CFLAGS_MODULE += -mlong-calls
diff --git a/arch/mips/kernel/r2300_switch.S b/arch/mips/kernel/r2300_switch.S
index 20b7b04..f33bf8b 100644
--- a/arch/mips/kernel/r2300_switch.S
+++ b/arch/mips/kernel/r2300_switch.S
@@ -22,6 +22,7 @@
#include <asm/asmmacro.h>
.set mips1
+ .set hardfloat
.align 5
/*
diff --git a/arch/mips/kernel/r4k_fpu.S b/arch/mips/kernel/r4k_fpu.S
index 8352523..722962c 100644
--- a/arch/mips/kernel/r4k_fpu.S
+++ b/arch/mips/kernel/r4k_fpu.S
@@ -21,6 +21,7 @@
.macro EX insn, reg, src
.set push
+ .set hardfloat
.set nomacro
.ex\@: \insn \reg, \src
.set pop
diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S
index 4c4ec18..5313b6f 100644
--- a/arch/mips/kernel/r4k_switch.S
+++ b/arch/mips/kernel/r4k_switch.S
@@ -34,6 +34,7 @@
* struct thread_info *next_ti, s32 fp_save)
*/
.align 5
+ .set hardfloat
LEAF(resume)
mfc0 t1, CP0_STATUS
LONG_S t1, THREAD_STATUS(a0)
diff --git a/arch/mips/kernel/r6000_fpu.S b/arch/mips/kernel/r6000_fpu.S
index da0fbe4..c13e3ff 100644
--- a/arch/mips/kernel/r6000_fpu.S
+++ b/arch/mips/kernel/r6000_fpu.S
@@ -17,6 +17,7 @@
#include <asm/regdef.h>
.set noreorder
+ .set hardfloat
.set mips2
/* Save floating point context */
LEAF(_save_fp_context)
--
2.0.4
