On Sat, Jul 16, 2022 at 2:54 PM Roger Sayle <ro...@nextmovesoftware.com> wrote: > > > This middle-end patch resolves PR c/106264 which is a spurious warning > regression caused by the tree-level expansion of modf, frexp and remquo > producing "expression has no-effect" when the built-in function's result > is ignored. When these built-ins were first expanded at tree-level, > fold_builtin_n would blindly set TREE_NO_WARNING for all built-ins. > Now that we're more discerning, we should precisely set TREE_NO_WARNING > selectively on those COMPOUND_EXPRs that need them. > > This patch has been tested on x86_64-pc-linux-gnu with make bootstrap > and make -k check with no new failures. Ok for mainline?
I think you should use suppress_warning (res); I can't think of a specific OPT_Wxyz to use so the end result should be the same. OK with that change. Richard. > 2022-07-16 Roger Sayle <ro...@nextmovesoftware.com> > > gcc/ChangeLog > PR c/106264 > * builtins.cc (fold_builtin_frexp): Set TREE_NO_WARNING on > COMPOUND_EXPR to silence spurious warning if result isn't used. > (fold_builtin_modf): Likewise. > (do_mpfr_remquo): Likewise. > > gcc/testsuite/ChangeLog > PR c/106264 > * gcc.dg/pr106264.c: New test case. > > > Thanks in advance, > Roger > -- >
