[Bug tree-optimization/78476] snprintf(0, 0, ...) with known arguments not optimized away

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78476

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
Created attachment 40122
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40122&action=edit
Patch under test.

Patch being tested (requires a patch for bug 78461).