| Message ID | 20191114095927.83723-1-roger.pau@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [for-4.13] x86/clang: move and fix .skip check | expand |
On 14.11.2019 10:59, Roger Pau Monne wrote: > .skip is only used by x86 code, so place the clang .skip with labels > check in x86/Rules.mk instead of the top level Rules.mk. While there > also fix an issue with it by removing the '\n' which triggers the > following error: > > <stdin>:1:31: error: missing terminating '"' character [-Werror,-Winvalid-pp-token] > void _(void) { asm volatile ( ".L0: > ^ > <stdin>:1:31: error: expected string literal in 'asm' > <stdin>:3:18: error: missing terminating '"' character [-Werror,-Winvalid-pp-token] > .skip (.L1 - .L0)" ); } > ^ > <stdin>:3:24: error: expected ')' > .skip (.L1 - .L0)" ); } > ^ > <stdin>:1:29: note: to match this '(' > void _(void) { asm volatile ( ".L0: > ^ > <stdin>:3:24: error: expected '}' > .skip (.L1 - .L0)" ); } > ^ > <stdin>:1:14: note: to match this '{' > void _(void) { asm volatile ( ".L0: > ^ > 5 errors generated. As said on the other thread - I'm afraid there's more to this difference in un-escaping between your and my environments. I agree the newlines aren't needed here at all, so I'd be fine to give my R-b, but we need to fully understand the differences in observed behavior anyway. Additionally I wonder whether you wouldn't better retain the original sequence of checks, by placing the check you move at the beginning of the "ifeq ($(clang),y)" block in x86/Rules.mk instead of at the end. That'll (iirc) also better represent the history of the addition of these checks (also demonstrated by the reference bug numbers). Jan
diff --git a/xen/Rules.mk b/xen/Rules.mk index 3090ea7828..d1c060c3cf 100644 --- a/xen/Rules.mk +++ b/xen/Rules.mk @@ -76,13 +76,6 @@ endif AFLAGS-y += -D__ASSEMBLY__ -# Older clang's built-in assembler doesn't understand .skip with labels: -# https://bugs.llvm.org/show_bug.cgi?id=27369 -ifeq ($(clang),y) -$(call as-option-add,CFLAGS,CC,".L0:\n.L1:\n.skip (.L1 - .L0)",,\ - -no-integrated-as) -endif - ALL_OBJS := $(ALL_OBJS-y) # Get gcc to generate the dependencies for us. diff --git a/xen/arch/x86/Rules.mk b/xen/arch/x86/Rules.mk index 659ac3d83e..328bbfea9d 100644 --- a/xen/arch/x86/Rules.mk +++ b/xen/arch/x86/Rules.mk @@ -83,4 +83,9 @@ $(call as-option-add,CFLAGS,CC,".include \"asm/indirect_thunk_asm.h\"",,\ $(call as-option-add,CFLAGS,CC,\ ".macro FOO\n.endm\"); asm volatile (\".macro FOO\n.endm",\ -no-integrated-as) + +# Older clang's built-in assembler doesn't understand .skip with labels: +# https://bugs.llvm.org/show_bug.cgi?id=27369 +$(call as-option-add,CFLAGS,CC,".L0: .L1: .skip (.L1 - .L0)",,\ + -no-integrated-as) endif
.skip is only used by x86 code, so place the clang .skip with labels check in x86/Rules.mk instead of the top level Rules.mk. While there also fix an issue with it by removing the '\n' which triggers the following error: <stdin>:1:31: error: missing terminating '"' character [-Werror,-Winvalid-pp-token] void _(void) { asm volatile ( ".L0: ^ <stdin>:1:31: error: expected string literal in 'asm' <stdin>:3:18: error: missing terminating '"' character [-Werror,-Winvalid-pp-token] .skip (.L1 - .L0)" ); } ^ <stdin>:3:24: error: expected ')' .skip (.L1 - .L0)" ); } ^ <stdin>:1:29: note: to match this '(' void _(void) { asm volatile ( ".L0: ^ <stdin>:3:24: error: expected '}' .skip (.L1 - .L0)" ); } ^ <stdin>:1:14: note: to match this '{' void _(void) { asm volatile ( ".L0: ^ 5 errors generated. Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> --- Cc: Juergen Gross <jgross@suse.com> --- NB: will need rebasing on top of Jan's patch (or the other way around). --- xen/Rules.mk | 7 ------- xen/arch/x86/Rules.mk | 5 +++++ 2 files changed, 5 insertions(+), 7 deletions(-)