https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80806
Bug ID: 80806 Summary: gcc does not warn if local array is memset only Product: gcc Version: 5.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: bugzi...@poradnik-webmastera.com Target Milestone: --- gcc has warning "variable ‘c’ set but not used". However this warning is not printed when local variable is cleared using memset, and then not used. Attempt to compile following code using gcc 5.4.0 prints warning regarding c var, but not regarding buf var: #include <string.h> void test() { char buf[10]; memset(buf, 0, sizeof(buf)); int c; c = 1; } $ gcc -c -O3 -Wall -Wextra test.c -o test.o test.c: In function ‘test’: test.c:8:9: warning: variable ‘c’ set but not used [-Wunused-but-set-variable] int c; ^