[BOLT] Force frame pointers off for runtimes #148009
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@llvm/pr-subscribers-bolt Author: Peter Waller (peterwaller-arm) ChangesDistributions are making the choice to turn frame pointers on by default. Nixpkgs recently turned them on, and the method they use to do so implies that everything is built with them on by default. Assuming that a well behaved distribution doing this puts See also: #147569 Full diff: https://github.com/llvm/llvm-project/pull/148009.diff 1 Files Affected:
diff --git a/bolt/runtime/CMakeLists.txt b/bolt/runtime/CMakeLists.txt
index 87cc44812da11..4c496c2b800ef 100644
--- a/bolt/runtime/CMakeLists.txt
+++ b/bolt/runtime/CMakeLists.txt
@@ -35,7 +35,10 @@ set(BOLT_RT_FLAGS
-fno-exceptions
-fno-rtti
-fno-stack-protector
- -fPIC)
+ -fPIC
+ -mgeneral-regs-only
+ -fomit-frame-pointer # Runtime currently assumes omitted frame pointers. llvm/llvm-project#147569
+)
if (CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64")
set(BOLT_RT_FLAGS ${BOLT_RT_FLAGS}
-mno-sse
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llvm-project/bolt/runtime/instr.cpp Line 1666 in dbb79c3 I currently suspect the issue is arising from Mentioning it in case anyone has an idea what's happening there, it looks like it relates to |
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@peterwaller-arm It looks like GCC just doesn't support naked functions on AArch64 at all, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77882. |
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Distributions are making the choice to turn frame pointers on by default. Nixpkgs recently turned them on, and the method they use to do so implies that everything is built with them on by default. NixOS/nixpkgs#399014 Assuming that a well behaved distribution doing this puts '-fno-omit-frame-pointer' at the beginning of the compiler invocation, we can still re-enable it by supplying -fomit-frame-pointer thereafter. See also: llvm#147569 Fixes: llvm#148595
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LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/153/builds/37967 Here is the relevant piece of the build log for the reference |
Distributions are making the choice to turn frame pointers on by default. Nixpkgs recently turned them on, and the method they use to do so implies that everything is built with them on by default.
NixOS/nixpkgs#399014
Assuming that a well behaved distribution doing this puts
-fno-omit-frame-pointerat the beginning of the compiler invocation, we can still re-enable omission by supplying-fomit-frame-pointerduring compilation.This fixes some segfaults from stack corruption in binaries rewritten by bolt with
llvm-bolt -instrument.See also: #147569
Fixes: #148595