JFTR, On Wed, 12 Nov 2025, Andrew Pinski wrote:
> ... > uninit-pred-5.C was actually a false positive because when > m_best_candidate is non-NULL, m_best_candidate_len is always initialized. > The log message on the testcase is wrong if you manually fall the path > you can notice that. With an extra jump threading after the merging of > some bbs, the false positive is now no longer happening. So change the > dg-warning to dg-bogus. But that's not true for all targets. > ssa-dom-thread-7.c now jump threads 12 times in thread2 instead of 8 > > Bootstrapped and tested on x86_64-linux-gnu. > > PR tree-optimization/122493 > gcc/ChangeLog: > > * tree-cfgcleanup.cc (tree_forwarder_block_p): Change bool argument > to a must have phi and allow phis if it is false. > (remove_forwarder_block): Add support for merging of forwarder blocks > with phis. > > gcc/testsuite/ChangeLog: > > * gcc.target/i386/pr121062-1.c: Update count. > * gcc.dg/uninit-pred-7_a.c: xfail line 23. > * g++.dg/uninit-pred-5.C: Change dg-warning to dg-bogus. > * gcc.dg/tree-ssa/ssa-dom-thread-7.c: Update count of jump thread. Since this commit, r16-5258, there's an XPASS for some targets, so I entered PR123377. FWIW, recently (2023), I made the regression/btest-gcc.sh scripts optionally handle XPASS as a FAIL, and I pass that option. I suggest people do that for their own test-scripts as well, as it seems XPASSes are largely ignored. HTH. HNY! brgds, H-P
