Messages in this thread Patch in this message | | | Date | Thu, 23 Apr 2020 19:30:58 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH] x86: Fix early boot crash on gcc-10, next try |
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On Thu, Apr 23, 2020 at 06:12:24PM +0200, Borislav Petkov wrote: > Ok, > > I have tried to summarize our odyssey so far and here's what I came up > with. Just built latest gcc from the git repo and it seems to work. > > Next I need to come up with a slick way of testing the compiler...
Maybe something like this. Seems to work with both.
--- From: Borislav Petkov <bp@suse.de> Date: Thu, 23 Apr 2020 19:28:28 +0200 Subject: [PATCH] Check compiler
Signed-off-by: Borislav Petkov <bp@suse.de> --- arch/x86/Makefile | 4 ++++ scripts/x86-check-compiler.sh | 9 +++++++++ 2 files changed, 13 insertions(+) create mode 100755 scripts/x86-check-compiler.sh
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 00e378de8bc0..38d3eec5062e 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -1,6 +1,10 @@ # SPDX-License-Identifier: GPL-2.0 # Unified Makefile for i386 and x86_64 +# Check the compiler +sane_compiler := $(shell $(srctree)/scripts/x86-check-compiler.sh $(CC)) +$(if $(sane_compiler),$(error $(CC) check failed. Aborting),) + # select defconfig based on actual architecture ifeq ($(ARCH),x86) ifeq ($(shell uname -m),x86_64) diff --git a/scripts/x86-check-compiler.sh b/scripts/x86-check-compiler.sh new file mode 100755 index 000000000000..b2b5b54b6939 --- /dev/null +++ b/scripts/x86-check-compiler.sh @@ -0,0 +1,9 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +# Check whether the compiler tail-call optimizes across an asm() statement. +# Fail the build if it does. + +echo "int foo(int a); int bar(int a) { int r = foo(a); asm(\"\"); return r; }" |\ + $* -O2 -x c -c -S - -o - 2>/dev/null |\ + grep -E "^[[:blank:]]+jmp[[:blank:]]+.*" -- 2.21.0 -- Regards/Gruss, Boris.
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