1. Source file (w.h): #if !defined __H__ #define _H__ #endif 2. Command line: clang -E w.h 3. Output: w.h:1:4: warning: '__H__' is used as a header guard here, followed by #define of a different macro [-Wheader-guard] Assertion failed: (StartColNo <= EndColNo && "Trying to highlight whitespace??"), function highlightRange, file /path/to/llvm-src/llvm/tools/clang/lib/Frontend/TextDiagnostic.cpp, line 973. Stack dump: 0. Program arguments: /path/to/installation/clang -cc1 -triple i386-unknown-freebsd10.0 -E -disable-free -main-file-name w.h -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -target-cpu i486 -target-linker-version 2.17.50 -resource-dir /path/to/installation/bin/../lib/clang/3.4 -fdebug-compilation-dir /dir1/dir2 -ferror-limit 19 -fmessage-length 255 -mstackrealign -fobjc-runtime=gnustep -fobjc-default-synthesize-properties -fdiagnostics-show-option -fcolor-diagnostics -backend-option -vectorize-loops -o - -x c-header w.h clang: error: unable to execute command: Abort trap (core dumped) clang: error: clang frontend command failed due to signal (use -v to see invocation) clang version 3.4 (trunk 184040) Target: i386-unknown-freebsd10.0 Thread model: posix clang: note: diagnostic msg: PLEASE submit a bug report to http://llvm.org/bugs/ and include the crash backtrace, preprocessed source, and associated run script. clang: error: unable to execute command: Abort trap (core dumped) clang: note: diagnostic msg: Error generating preprocessed source(s).
See also bug 15741.
Fixed in r184054.