From: shyouhei@... Date: 2021-03-02T01:08:13+00:00 Subject: [ruby-core:102688] [Ruby master Bug#17540] A segfault due to Clang/LLVM optimization on 32-bit ARM Linux Issue #17540 has been updated by shyouhei (Shyouhei Urabe). I suspect commit:d0e0c884bb4277e529adbd8d82aae0a651f7edf2 could be the cause of this issue. ---------------------------------------- Bug #17540: A segfault due to Clang/LLVM optimization on 32-bit ARM Linux https://bugs.ruby-lang.org/issues/17540#change-90683 * Author: xtkoba (Tee KOBAYASHI) * Status: Open * Priority: Normal * ruby -v: ruby 3.0.0p0 (2020-12-25 revision 95aff21468) [armv7a-linux-eabi] * Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN ---------------------------------------- When built with `optflags=-O3` (which is the default), `ruby -e "pp Thread.main"` causes a segfault, which seems to be worked around by the following change: ``` --- a/include/ruby/internal/fl_type.h +++ b/include/ruby/internal/fl_type.h @@ -231,7 +231,7 @@ RBIMPL_ATTR_PURE_UNLESS_DEBUG() RBIMPL_ATTR_ARTIFICIAL() static inline VALUE -RB_FL_TEST_RAW(VALUE obj, VALUE flags) +RB_FL_TEST_RAW(volatile VALUE obj, VALUE flags) { RBIMPL_ASSERT_OR_ASSUME(RB_FL_ABLE(obj)); return RBASIC(obj)->flags & flags; ``` There might be a bug in the optimizer of Clang/LLVM (version 11.0.1). -- https://bugs.ruby-lang.org/ Unsubscribe: