On Fri, Jan 19, 2018 at 8:26 AM, Mikhail Maltsev <maltsevm@xxxxxxxxx> wrote: > On Fri, Jan 19, 2018 at 1:16 PM, Matt Sexton via gcc-help < > gcc-help@xxxxxxxxxxx> wrote: > >> At this point, I do not have a small piece of code that I can share that >> triggers the problem, though I will try to do so. >> > You might want to try to use https://embed.cs.utah.edu/creduce/ to > generate such a piece of code from your source automatically. See also: > https://gcc.gnu.org/wiki/A_guide_to_testcase_reduction > >> >> Great suggestion. What a brilliant tool. It reduced the test case to the following: $ cat bug.c typedef struct { struct { int a[0] } } b; typedef struct { int c } d; __thread d e; f; g() { b *h = &e.c; int *a = h->a; i(a[f]); i(a[f]); } $ x86_64-w64-mingw32-gcc -O2 bug.c bug.c:4:3: warning: no semicolon at end of struct or union } ^ bug.c:5:1: warning: no semicolon at end of struct or union } b; ^ bug.c:6:24: warning: no semicolon at end of struct or union typedef struct { int c } d; ^ bug.c:8:1: warning: data definition has no type or storage class f; ^ bug.c:8:1: warning: type defaults to 'int' in declaration of 'f' [-Wimplicit-int] bug.c:9:1: warning: return type defaults to 'int' [-Wimplicit-int] g() { ^ bug.c: In function 'g': bug.c:10:10: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types] b *h = &e.c; ^ bug.c:12:3: warning: implicit declaration of function 'i' [-Wimplicit-function-declaration] i(a[f]); ^ bug.c:9:1: internal compiler error: in get_constraint_for_ptr_offset, at tree-ssa-structalias.c:3155 g() { ^ Please submit a full bug report, with preprocessed source if appropriate. See <http://bugzilla.redhat.com/bugzilla> for instructions.
