Crash to LDB in backtrace from internal-error when built with gcc-4.3
Found this one on a lightly-loaded test server. If the SBCL runtime is compiled with gcc-4.3 (but not with gcc-4.4), and a GC occurs while doing a backtrace when there's an internal-error trap context on the stack, the system fails a GC assertion at the bottom of scavenge(). Found on 22.214.171.124 (x86), confirmed on 1.0.23 (x86-64), 1.0.35 (x86), and 126.96.36.199 (x86).
Again, this only happens when compiling with gcc-4.3, and I have only tested on x86 and x86-64 linux boxes.
My primary questions are: Why does this happen? Why doesn't it happen with gcc-4.4? And, finally, how do we know that nothing similar (or worse) happens in such scenarios, regardless of which compiler is used?
(running SBCL from: /home/nyef/
This is SBCL 188.8.131.52-1a104ef, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://
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(:ANSI-CL :COMMON-LISP :SBCL :SB-DOC :SB-TEST :SB-LDB :SB-PACKAGE-LOCKS
:SB-UNICODE :SB-EVAL :SB-SOURCE-
:OS-PROVIDES-PUTWC :OS-PROVIDES-DLADDR :OS-PROVIDES-DLOPEN :LITTLE-ENDIAN
:LINKAGE-TABLE :MULTIPLY-HIGH-VOPS :MEMORY-
:CYCLE-COUNTER :ALIEN-CALLBACKS :STACK-
:LINUX :ELF :UNIX :X86)
; compiling file "/home/
; compiling (DEFUN TESTFUN ...)
; compiling (DEFUN MAYBE-DIE ...)
; compiling (DEFUN TRY-BACKTRACE ...)
; compiling (DEFUN TRY-TO-BREAK ...)
; compilation finished in 0:00:00.058
* Final object pointer 0x18e441d0, start 0xc722000, end 0xc722270
fatal error encountered in SBCL pid 1834(tid 4158908096):
GC invariant lost, file "gc-common.c", line 191
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