* [Qemu-devel] [PULL 1/2] linux-user: Fix i386 safe-syscall.S
2016-07-10 17:10 [Qemu-devel] [PULL 0/2] build fix for clang 3.4 Richard Henderson
@ 2016-07-10 17:10 ` Richard Henderson
2016-07-10 17:10 ` [Qemu-devel] [PULL 2/2] build: Use $(AS) for optionrom explicitly Richard Henderson
2016-07-11 14:06 ` [Qemu-devel] [PULL 0/2] build fix for clang 3.4 Peter Maydell
2 siblings, 0 replies; 4+ messages in thread
From: Richard Henderson @ 2016-07-10 17:10 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell
Clang insists that "cmp" is ambiguous with a memory destination,
requiring an explicit size suffix.
There was a true error in the use of .cfi_def_cfa_offset in the
epilogue, but changing to use the proper .cfi_adjust_cfa_offset
runs afoul of a clang bug wrt .cfi_restore_state. Better to
fold the two epilogues so that we don't trigger the bug.
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
linux-user/host/i386/safe-syscall.inc.S | 24 ++++++------------------
1 file changed, 6 insertions(+), 18 deletions(-)
diff --git a/linux-user/host/i386/safe-syscall.inc.S b/linux-user/host/i386/safe-syscall.inc.S
index 766d0de..9e58fc6 100644
--- a/linux-user/host/i386/safe-syscall.inc.S
+++ b/linux-user/host/i386/safe-syscall.inc.S
@@ -69,7 +69,7 @@ safe_syscall_base:
safe_syscall_start:
/* if signal_pending is non-zero, don't do the call */
mov 4+16(%esp), %eax /* signal_pending */
- cmp $0, (%eax)
+ cmpl $0, (%eax)
jnz 1f
mov 8+16(%esp), %eax /* syscall number */
int $0x80
@@ -77,16 +77,16 @@ safe_syscall_end:
/* code path for having successfully executed the syscall */
pop %ebx
.cfi_remember_state
- .cfi_def_cfa_offset -4
+ .cfi_adjust_cfa_offset -4
.cfi_restore ebx
pop %edi
- .cfi_def_cfa_offset -4
+ .cfi_adjust_cfa_offset -4
.cfi_restore edi
pop %esi
- .cfi_def_cfa_offset -4
+ .cfi_adjust_cfa_offset -4
.cfi_restore esi
pop %ebp
- .cfi_def_cfa_offset -4
+ .cfi_adjust_cfa_offset -4
.cfi_restore ebp
ret
@@ -94,19 +94,7 @@ safe_syscall_end:
/* code path when we didn't execute the syscall */
.cfi_restore_state
mov $-TARGET_ERESTARTSYS, %eax
- pop %ebx
- .cfi_def_cfa_offset -4
- .cfi_restore ebx
- pop %edi
- .cfi_def_cfa_offset -4
- .cfi_restore edi
- pop %esi
- .cfi_def_cfa_offset -4
- .cfi_restore esi
- pop %ebp
- .cfi_def_cfa_offset -4
- .cfi_restore ebp
- ret
+ jmp safe_syscall_end
.cfi_endproc
.size safe_syscall_base, .-safe_syscall_base
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [Qemu-devel] [PULL 2/2] build: Use $(AS) for optionrom explicitly
2016-07-10 17:10 [Qemu-devel] [PULL 0/2] build fix for clang 3.4 Richard Henderson
2016-07-10 17:10 ` [Qemu-devel] [PULL 1/2] linux-user: Fix i386 safe-syscall.S Richard Henderson
@ 2016-07-10 17:10 ` Richard Henderson
2016-07-11 14:06 ` [Qemu-devel] [PULL 0/2] build fix for clang 3.4 Peter Maydell
2 siblings, 0 replies; 4+ messages in thread
From: Richard Henderson @ 2016-07-10 17:10 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell
For clang before 3.5, -fno-integrated-as does not exist,
so the workaround in 5f6f0e27fb24 fails to build.
Use clang's default assembler for linux-user/safe-syscall.S,
and explicitly change to use the system assembler for the
option roms.
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
configure | 10 +++-------
pc-bios/optionrom/Makefile | 3 +++
rules.mak | 2 +-
3 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/configure b/configure
index e9090a0..5ada56d 100755
--- a/configure
+++ b/configure
@@ -368,6 +368,7 @@ else
fi
ar="${AR-${cross_prefix}ar}"
+as="${AS-${cross_prefix}as}"
ccas="${CCAS-$cc}"
cpp="${CPP-$cc -E}"
objcopy="${OBJCOPY-${cross_prefix}objcopy}"
@@ -4490,13 +4491,6 @@ if test "$fortify_source" != "no"; then
fi
fi
-#################################################
-# clang does not support the 16-bit assembly for roms
-
-if echo | $ccas -dM -E - | grep __clang__ > /dev/null 2>&1 ; then
- ccas="$ccas -fno-integrated-as"
-fi
-
##########################################
# check if struct fsxattr is available via linux/fs.h
@@ -5515,6 +5509,7 @@ echo "CXX=$cxx" >> $config_host_mak
echo "OBJCC=$objcc" >> $config_host_mak
echo "AR=$ar" >> $config_host_mak
echo "ARFLAGS=$ARFLAGS" >> $config_host_mak
+echo "AS=$as" >> $config_host_mak
echo "CCAS=$ccas" >> $config_host_mak
echo "CPP=$cpp" >> $config_host_mak
echo "OBJCOPY=$objcopy" >> $config_host_mak
@@ -5988,6 +5983,7 @@ for rom in seabios vgabios ; do
config_mak=roms/$rom/config.mak
echo "# Automatically generated by configure - do not modify" > $config_mak
echo "SRC_PATH=$source_path/roms/$rom" >> $config_mak
+ echo "AS=$as" >> $config_mak
echo "CCAS=$ccas" >> $config_mak
echo "CC=$cc" >> $config_mak
echo "BCC=bcc" >> $config_mak
diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile
index ce4852a..2cdda87 100644
--- a/pc-bios/optionrom/Makefile
+++ b/pc-bios/optionrom/Makefile
@@ -20,6 +20,9 @@ build-all: multiboot.bin linuxboot.bin kvmvapic.bin
# suppress auto-removal of intermediate files
.SECONDARY:
+%.o: %.S
+ $(call quiet-command,$(CPP) $(QEMU_INCLUDES) $(QEMU_DGFLAGS) $(CFLAGS) -c -o - $< | $(AS) $(ASFLAGS) -o $@," AS $(TARGET_DIR)$@")
+
%.img: %.o
$(call quiet-command,$(LD) $(LDFLAGS_NOPIE) -Ttext 0 -e _start -s -o $@ $<," Building $(TARGET_DIR)$@")
diff --git a/rules.mak b/rules.mak
index 7d7d83b..ed8e482 100644
--- a/rules.mak
+++ b/rules.mak
@@ -69,7 +69,7 @@ LINK = $(call quiet-command, $(LINKPROG) $(QEMU_CFLAGS) $(CFLAGS) $(LDFLAGS) -o
$(version-obj-y) $(call extract-libs,$1) $(LIBS)," LINK $(TARGET_DIR)$@")
%.o: %.S
- $(call quiet-command,$(CCAS) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c -o $@ $<," AS $(TARGET_DIR)$@")
+ $(call quiet-command,$(CCAS) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c -o $@ $<," CCAS $(TARGET_DIR)$@")
%.o: %.cc
$(call quiet-command,$(CXX) $(QEMU_INCLUDES) $(QEMU_CXXFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) $($@-cflags) -c -o $@ $<," CXX $(TARGET_DIR)$@")
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread