On 12/05/2017 04:47 PM, Martin Sebor wrote: > PR middle-end/82646 - bogus -Wstringop-overflow with > -D_FORTIFY_SOURCE=2 on strncpy with range to a member array, > > The bug points out a false positive in a call to strncpy() when > _FORTIFY_SOURCE is defined that doesn't exist otherwise. > > The problem is that __builtin_strncpy buffer overflow checking > is done along with the expansion of the intrinsic in one place > and __builtin___strncpy_chk is handled differently in another, > and the two are out of sync. > > The attached patch corrects the choice of arguments used for > overflow detection in __builtin___strncpy_chk and aligns > the diagnostics between the two intrinsics. > > Martin > > gcc-82646.diff > > > PR tree-optimization/82646 - bogus -Wstringop-overflow with > -D_FORTIFY_SOURCE=2 on strncpy with range to a member array > > gcc/ChangeLog: > > PR tree-optimization/82646 > * builtins.c (maybe_emit_chk_warning): Use size as the bound for > strncpy, not maxlen. > > gcc/testsuite/ChangeLog: > > PR tree-optimization/82646 > * gcc.dg/builtin-stringop-chk-1.c: Adjust. > * gcc.dg/builtin-stringop-chk-9.c: New test. OK.
[ Happy to see something easy fly by that isn't SVE related :-) ] jeff
