From 18edc195442291525e04f0fa4d5ef972155117da Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Wed, 13 May 2020 11:22:37 +0200 Subject: Fix -fcompare-debug issue in purge_dead_edges [PR95080] The following testcase fails with -fcompare-debug, the bug used to be latent since introduction of -fcompare-debug. The loop at the start of purge_dead_edges behaves differently between -g0 and -g - if the last insn is a DEBUG_INSN, then it skips not just DEBUG_INSNs but also NOTEs until it finds some other real insn (or bb head), while with -g0 it will not skip any NOTEs, so if we have real_insn note debug_insn // not present with -g0 then with -g it might remove useless REG_EH_REGION from real_insn, while with -g0 it will not. Yet another option would be not skipping NOTE_P in the loop; I couldn't find in history rationale for why it is done. 2020-05-13 Jakub Jelinek PR debug/95080 * cfgrtl.c (purge_dead_edges): Skip over debug and note insns even if the last insn is a note. * g++.dg/opt/pr95080.C: New test. --- gcc/cfgrtl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'gcc/cfgrtl.c') diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c index e6ea687ef31..827e84a44dd 100644 --- a/gcc/cfgrtl.c +++ b/gcc/cfgrtl.c @@ -3100,7 +3100,7 @@ purge_dead_edges (basic_block bb) bool found; edge_iterator ei; - if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb)) + if ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)) do insn = PREV_INSN (insn); while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb)); -- cgit v1.2.1