On Wed, Aug 19, 2026 at 10:22 PM Roger Sayle <[email protected]> wrote: > > > This patch fixes PR middle-end/126775, an ICE caused by my recent change > to match.pd around tweaking the conditions under which 0.0 - x can > safely be transformed into -x. Unfortunately, that change assumed > that real_zerop@0 implies that TREE_CODE(@0) == REAL_CST. Alas things > aren't that simple, so this fix introduces a new real_negzerop predicate > that in addition to REAL_CST also handles VECTOR_CST and COMPLEX_CST, > and most importantly fails gracefully on TREE_CODEs that it isn't > expecting. > > This patch has been tested on x86_64-pc-linux-gnu with make bootstrap > and make -k check, both with and without --target_board=unix{-m32} > with no new failures. Ok for mainline?
OK. Thanks, Richard. > > 2026-08-19 Roger Sayle <[email protected]> > > gcc/ChangeLog > PR middle-end/126775 > * match.pd (0.0 - x -> -x): Use new real_negzerop function. > * tree.cc (real_negzerop): New predicate function to test if > a tree expression is -0.0 or equivalent (like real_zerop). > * tree.h (real_negzerop): Prototype here. > > gcc/testsuite/ChangeLog > PR middle-end/126775 > * gcc.dg/pr126775.c: New test case. > > > Thanks again, and apologies for any inconvenice. > Roger > -- >
