https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82101
Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|FIXED |--- Known to fail| |10.2.0, 11.0, 7.3.0, 8.3.0, | |9.2.0 Last reconfirmed|2017-09-05 00:00:00 |2021-4-2 Status|RESOLVED |NEW --- Comment #4 from Martin Sebor <msebor at gcc dot gnu.org> --- Let me take that back. The complaint is about the missing warning for the variable in the loop, not the one outside it, and presumably with -O1 or above. That's not quite clear from the description. Here's a test case for the problem. It's never been diagnosed: $ cat pr82101.C && gcc -O1 -S -Wall pr82101.C void f (int); void g (void) { for (int i = 0; i < 10; i++) { int t = t; // -Wuninitialized f (t); } } void h (void) { for (int i = 0; i < 10; i++) { int t = t; // missing warning } } pr82101.C: In function ‘void g()’: pr82101.C:8:9: warning: ‘t’ is used uninitialized [-Wuninitialized] 8 | f (t); | ~~^~~ pr82101.C:7:11: note: ‘t’ was declared here 7 | int t = t; // -Wuninitialized | ^