[Bug middle-end/64920] bootstrap-ubsan [build/gengtype -r gtype.state]: libiberty/regex.c:6970:11: runtime error: left shift of negative value -1

[zeccav at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64920

Vittorio Zecca <zeccav at gmail dot com> changed:

           What    |Removed                     |Added
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                 CC|                            |zeccav at gmail dot com

--- Comment #1 from Vittorio Zecca <zeccav at gmail dot com> ---
I have the same messages during gcc 5.2.0 generation

Fixing directory /usr/include into
/home/vitti/gcc-5.2.0-sanitize-all/gcc/include-fixed
../../../gcc-5.2.0/libiberty/regex.c:6972:11: runtime error: left shift of
negative value -1
../../../gcc-5.2.0/libiberty/regex.c:7167:4: runtime error: left shift of
negative value -1
Applying machine_name             to slang.h

I believe this is because at line 688

(destination) += SIGN_EXTEND_CHAR (*((source) + 1)) << 8;

(*((source) + 1)) is negateive (-1)