[Bug sanitizer/80932] UBSAN: false positive as a result of distribution: c1*(c2*v1-c3*v2)=>c1*c2*v1-c1*c3*v2

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80932

--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Author: mpolacek
Date: Wed Jun  7 11:19:40 2017
New Revision: 248961

URL: https://gcc.gnu.org/viewcvs?rev=248961&root=gcc&view=rev
Log:
        PR sanitizer/80932
        * fold-const.c (extract_muldiv_1) <case MINUS_EXPR>: Add
        TYPE_OVERFLOW_WRAPS check. 

        * c-c++-common/ubsan/pr80932.c: New test.

Added:
    trunk/gcc/testsuite/c-c++-common/ubsan/pr80932.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/fold-const.c
    trunk/gcc/testsuite/ChangeLog