https://gcc.gnu.org/bugzilla/show_bug.cgi?id=44263
Eric Gallager <egallager at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2017-09-26 CC| |egallager at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #2 from Eric Gallager <egallager at gcc dot gnu.org> --- I get a warning for g with -pedantic: $ /usr/local/bin/g++ -c -Wall -Wextra -pedantic 44263.cc 44263.cc: In function ‘void foo()’: 44263.cc:12:39: warning: size of array is not an integral constant-expression [-Wpedantic] char g[(char *) &((struct S *) 0)->b - (char *) 0]; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~ $ But I'm assuming you're still requesting another warning for h? Confirmed in that case.