Open Source Bug Reports by

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Much of my time when working on these bugs was paid for by my ex-employer, PalmSource, which was endeavoring to give back to the Open Source community, but I was not officially representing PalmSource in these contributions. For the techniques used to find many of these bugs, see “Practical Testing of a C99 Compiler Using Output Comparison,” Software: Practice and Experience April 2007 (preprint at

Contributed Code & Documentation

  1. Linux Test Project: runltp 1.6: Run only specified test cases
  2. apple/swift: my Commits, GitHub (svn r9634-r24586)
  3. Scala: Add a Partest option to use a different compiler
  4. LLVM: Explain code coverage with Lit in docs/SourceBasedCodeCoverage.rst
  5. evcxr_repl, a Rust REPL: Allow extra command line arguments (N.b., I am not a Rust programmer — I needed this to start learning.)
  6. Alive2: Variablize uses of ~/llvm in the build instructions, add the obvious Ninja build steps
  7. Alive2: Use real files
  8. Alive2: Troubleshooting Mac dynamic_lookup/chained fixups linker warning
  9. Alive2: Report CMAKE_PREFIX_PATH, detecting unsound transformations in a local run, CMake may look in /opt/, tightly coupled to LLVM top of tree source

GCC Bug Reports

    GCC 3.3

  1. GCC bug 15549: true !< 'a'
  2. GCC Bug 21659: "weak declaration must precede definition" error missing at >= O2
  3. GCC bug 23472: __attribute__((constructor)) called twice with -funit-at-a-time

    GCC 3.4

  4. GCC bug 15642: NAN Is Not a Constant Because __APPLE_CC__ is Not Defined (OK in Apple 3.3.0)
  5. Apple GCC bug: 666675 : math.h tests __APPLE_CC__ instead of __GNUC__
  6. GCC bug 21613 - -fpic only: internal compiler error: in extract_insn, at recog.c:2083 (20010107-1.c:6)
  7. GCC bug 24075 (ARM): Destructor called with wrong argument after exception with -fcse-follow-jumps -O1
  8. GCC bug 24322: Segmentation fault or out of memory compiling FFMpeg snow.c at -O3 for ARM
  9. GCC bug 27829 (ARM): ICE/abort in shift_op, at config/arm/arm.c:7917 with asm from testsuite/gcc.dg/pr21255-2-mb.c

    GCC 4.0.0

  10. GCC Bug 22320: -ftree-dominator-opts documentation is the same as -ftree-dce

    GCC 4.0.1

  11. GCC Bug 22508: [4.0/4.1 Regression] ICE after invalid operator new, segmentation fault or EXC_BAD_ACCESS with modified Eckel sample code
  12. GCC bug 22600 - Exit code should be different from 1 for internal compiler error (ICE_EXIT_CODE)
  13. GCC bug 22603 - internal compiler error: in pop_binding, at cp/name-lookup.c:380
  14. GCC bug 22604 - Segmentation fault after invalid covariant return
  15. GCC bug 23089 - internal compiler error: in int_mode_for_mode, at stor-layout.c:251 at -O1
  16. GCC bug 23118 - Another segmentation fault after improper overloading (BootView)
  17. GCC bug 23125 - OpenBSD's zic.c causes g++ but not gcc to segfault
  18. GCC bug 23223 - Segfault part 3, after typedef
  19. GCC bug 23225 - tree check: expected class type, have exceptional (error_mark) in build_pointer_type_for_mode, at tree.c:4246
  20. Bug 23307: ICE in cp_parser_template_id, at cp/parser.c:8564 with Boost remote_call_manager
  21. GCC bug 23430: --with-comment configure option isn't documented

    GCC 4.1.0

  22. GCC bug 26774: Out of memory compiling 9-line Delta-reduced Linux kernel driver msp3400.c
  23. GCC bug 26818: tree check: expected class 'type', have 'exceptional' (error_mark) in finish_struct, at c-decl.c:5350 (time.c)
  24. GCC bug 26865: Segmentation fault with -std=c99 -O1 on genksyms.c

    GCC 4.1.1

  25. GCC Bug 27851: Hour-long segfault with -O1 -g on gcc.dg/parm-impl-decl-1.c
  26. GCC Bug 27881: Memory exhausted with -finline-functions on testsuite file alias3.C

CodeSourcery ARM GCC

  1. [arm-gnu] gnueabi-g++: Segmentation fault; glibc detected *** free(): invalid pointer
  2. [arm-gnu] Segmentation fault compiling empty .ii file
  3. CodeSourcery bug 401: Segfault with -ftracer -O2 -funswitch-loops
  4. CodeSourcery bug 434: Overflowed ullong prints incorrect value
  5. CodeSourcery bug 440: llong_Min / 2 => -7B9Aca0000000000, not -4000000000000000
  6. CodeSourcery bug 444: DBL_MIN with -fsingle-precision-constant => 0.0
  7. CodeSourcery bug 456: unrecognizable insn in extract_insn, at recog.c:2083
  8. CodeSourcery bug 458: unrecognizable insn in gdb.threads/tls.c:119 with -O3 -fpic
  9. CodeSourcery bug 500: printf INT_MIN / -1 gives random value
  10. CodeSourcery bug 502: volatile 1ULL/INT_MIN => 1 not 0
  11. CodeSourcery bug 726: gcc_unreachable reached with asm from testsuite/gcc.dg/pr21255-2-mb.c (cp. GCC bug 27829)

LLVM Bug Reports

  1. asan heap-use-after-free for GlobalISel/arm64-atomic.ll with --compile-twice #61462
  2. llvm-cov -path-equivalence is broken #62689
  3. [BFI][CGP] Assertion failed: (Match && "BFI mismatch"), function verifyMatch, file BlockFrequencyInfoImpl.h #64197 (Diagnosed and reported by Pavel Kopyl, detected by my --cgp-verify-bfi-updates test)
  4. should exit with a failure code when there are errors #65000
  5. clang-tidy fails with “Error: no checks enabled” on .clang-tidy file which --verify-config verifies #86355
  6. tblgen-lsp-server --help usage omits needed redirect #92614

Alive2 Bug Report

  1. False negative in LoopVectorizePass on runtime-checks-difference.ll in Compiler Explorer instance (Don’t rely on the Compiler Explorer instance of Alive.)


  1. Bug 82635 - SWT Application Tutorial VM args text is not selectable

    Cloned by Brad Jarvinen

  2. Bug 78677 - Text drag and drop in C/C++ editor window
  3. Bug 78563 - Better line numbering display in C/C++ editor
  4. Bug 69230 - Find not enabled in console C-Build view
  5. Bug 75485 - Syntax highlighting of <float.h> is incorrect
  6. Bug 78670 - CDT should support .c++ file extension
  7. Bug 92857 - Enable Split view in C Source editor window


  1. GDB bug 1831: Configure failure on Mac OSX is insufficiently prominent
  2. GDB bug 1959: ARMulator hangs running executable with wrong ABI
  3. CodeSourcery bug 531: GDB ARM shows infinite backtrace for breakpoint in thread function
  4. GDB bug 2072: "info files" says "serial" twice when remote debugging via TCP
  5. GDB bug 2074: The maximum number of target hardware breakpoints is 4294967295.
  6. CodeSourcery bug 553: "Previous frame identical to this frame (corrupt stack?)" after crash in printf
  7. GDB bug 2090: ARM/TUI: Segfault pressing up-arrow with missing source


  1. Hello world example won't report failure
  2. Illegal Argument "--connect"

Other Bug Reports

  1. Linux Test Project bug 1106474: Segmentation fault in syslog01 on Suse 9.2 under runltp
  2. KDevelop bug 105498: Kernel module wizard file name inconsistency (KDE KDevelop)
  3. Sudo bug 165: Wal-Mart/Microtel/Xandros sudo skips authentication
  4. Plucker 1517: Paragraph indentation option
  5. Expect bug 1255416: checking for tclInt.h...Can't find Tcl private headers
  6. FindBugs 1907539: 22 minor errors in bug checker documentation
  7. FindBugs 1942620: Source Directories selection dialog interface confusion
  8. LaTeX: unicode-math doesn't output “ƒ” in math mode
  9. Solidity: --evmonepath option for non-Linux platforms

Other People's Relevant Bug Reports

  1. GDB bug 1884: arm-none-elf target sim does not run ARM executables [ARMulator]
  2. GDB bug 1914: gdb does not notice dynamic library loads when attached to running process
  3. GCC Bug 16586 - [3.4 Regression] -O3 -fno-gcse ICE verify_local_live_at_start flow.c:575
  4. GCC bug 20161 - [4.0/4.1 Regression] ICE with dwarf for incomplete element type argument
  5. GCC bug 22008 - [4.0/4.1 Regression] ICE on valid code, create_tmp_var: in create_tmp_var, at gimplify.c:368 (Postponed until 4.0.2)
  6. GCC bug 16717: __attribute__((constructor)) broken in C++ [with unit-at-a-time, fixed in 3.4.2]
  7. GCC bug 17810: internal compiler error: in verify_local_live_at_start for arm-rtems, arm-linux
  8. GCC bug 12133: Reload abort in simd-3.c (Reported in 3.4.0, postponed to 4.0.0)
  9. GCC bug 16676: [3.4 Regression] ICE with nested functions and -g1, blocks glibc (likely not to be fixed in 3.x)
  10. GCC bug 26881: [4.1/4.2 Regression] internal compiler error in dwarf2out_finish
  11. Eclipse bug 122705: Format of variables is reset to "Natural" after a breakpoint hit (filed by Ewa Matejska)
  12. GDB bug 1091: Constructor breakpoints ignored