diff options
Diffstat (limited to 'etc/DEBUG')
| -rw-r--r-- | etc/DEBUG | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/etc/DEBUG b/etc/DEBUG index dd33b42f19a..7d2f810d078 100644 --- a/etc/DEBUG +++ b/etc/DEBUG @@ -947,10 +947,10 @@ several kinds of low-level problems in C code, including: * Passing invalid values to some builtin functions, e.g., __builtin_clz (0). * Reaching __builtin_unreachable calls (in Emacs, 'eassume' failure). -To use UndefinedBehaviorSanitizer with GCC and similar compilers, -append '-fsanitize=undefined' to CFLAGS, either when running -'configure' or running 'make'. When supported, you can also specify -'bound-strict' and 'float-cast-overflow'. For example: +To use GCC's UndefinedBehaviorSanitizer, append '-fsanitize=undefined' +to CFLAGS, either when running 'configure' or running 'make'. +When supported, you can also specify 'bound-strict' and +'float-cast-overflow'. For example: ./configure \ CFLAGS='-O0 -g3 -fsanitize=undefined,bounds-strict,float-cast-overflow' @@ -958,6 +958,11 @@ append '-fsanitize=undefined' to CFLAGS, either when running You may need to append '-static-libubsan' to CFLAGS if your version of GCC is installed in an unusual location. +Clang's UB sanitizer can also be used, but has coverage problems. +You'll need '-fsanitize=undefined -fno-sanitize=pointer-overflow' to +suppress misguided warnings about adding zero to a null pointer, +although this also suppresses any valid pointer overflow warnings. + When using GDB to debug an executable with undefined-behavior sanitization, the GDB command: |