MaskRay added a comment. In D72222#1837358 <https://reviews.llvm.org/D72222#1837358>, @nickdesaulniers wrote:
> In D72222#1837184 <https://reviews.llvm.org/D72222#1837184>, @MaskRay wrote: > > > @peter.smith The build was smooth. Do I need other options to reproduce? > > > I was able to reproduce: > > $ git clone --depth 1 > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git > $ cd linux-next > $ ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang -j71 > allyesconfig > $ ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang -j71 > mm/kasan/quarantine.o > > > The exact compiler invocation (via tacking on `V=1` to the above `make` > command is: > > $ clang -Wp,-MD,mm/kasan/.quarantine.o.d -nostdinc -isystem > /android0/llvm-project/llvm/build/lib/clang/11.0.0/include > -I./arch/arm64/include -I./arch/arm64/include/generated -I./include > -I./arch/arm64/include/uapi -I./arch/arm64/include/generated/uapi > -I./include/uapi -I./include/generated/uapi -include > ./include/linux/kconfig.h -include ./include/linux/compiler_types.h > -D__KERNEL__ -mlittle-endian -DCC_USING_PATCHABLE_FUNCTION_ENTRY > -DKASAN_SHADOW_SCALE_SHIFT=3 -Qunused-arguments -Wall -Wundef > -Werror=strict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common > -fshort-wchar -fno-PIE -Werror=implicit-function-declaration > -Werror=implicit-int -Wno-format-security -std=gnu89 > --target=aarch64-linux-gnu --prefix=/usr/bin/ --gcc-toolchain=/usr > -no-integrated-as -Werror=unknown-warning-option -mgeneral-regs-only > -DCONFIG_CC_HAS_K_CONSTRAINT=1 -fno-asynchronous-unwind-tables > -DKASAN_SHADOW_SCALE_SHIFT=3 -fno-delete-null-pointer-checks > -Wno-address-of-packed-member -O2 -Wframe-larger-than=2048 > -fstack-protector-strong -Wno-format-invalid-specifier -Wno-gnu > -Wno-tautological-compare -mno-global-merge -Wno-unused-const-variable > -fno-omit-frame-pointer -fno-optimize-sibling-calls > -ftrivial-auto-var-init=pattern -fpatchable-function-entry=2 > -Wdeclaration-after-statement -Wvla -Wno-pointer-sign -fno-strict-overflow > -fno-merge-all-constants -fno-stack-check -Werror=date-time > -Werror=incompatible-pointer-types -fmacro-prefix-map=./= > -Wno-initializer-overrides -Wno-format -Wno-sign-compare > -Wno-format-zero-length -fno-builtin > -DKBUILD_MODFILE='"mm/kasan/quarantine"' -DKBUILD_BASENAME='"quarantine"' > -DKBUILD_MODNAME='"quarantine"' -c -o mm/kasan/quarantine.o > mm/kasan/quarantine.c > > creduce spits out: > > > // $ clang -O2 quarantine.i > __attribute__((patchable_function_entry(0))) a() { > > b(({ > c: > &&c; > })); > > } > > Thanks. Looks like the following is sufficient to reproduce. (I incorrectly thought an empty entry MachineBasicBlock was impossible.) I take the opportunity to add test coverage (testing debug-location: D73301 <https://reviews.llvm.org/D73301>) define void @foo() #0 { entry: unreachable } attributes #0 = { "patchable-function-entry"="2" } A -DLLVM_ENABLE_ASSERTIONS=on build is required to trigger the assertion failure. My `make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- HOSTGCC=gcc CC=~/llvm/ReleaseAssert/bin/clang LD=~/llvm/ReleaseAssert/bin/ld.lld O=/tmp/arm64 allmodconfig all -j 30` build succeeded. Now I will be in favor of pushing the bugfix to release/10.x . Not clear about -fpatchable-function-entry=N,M where M>0 (D73070 <https://reviews.llvm.org/D73070>, D73071 <https://reviews.llvm.org/D73071>, D73072 <https://reviews.llvm.org/D73072>). For completeness, I'd like them to be included in release/10.x so we will not have a clang 10 that does not work with M>0. For `BTI c` issue, GCC has several releases that do not work with -mbranch-protection=bti. The Linux kernel has to develop some mechanism to detect the undesirable placement of `bti c`, if there are -mbranch-protection=bti users. So I don't think that inconsistency in clang 10.0.0 with GCC will be a problem. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D72222/new/ https://reviews.llvm.org/D72222 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
