[gcc r15-10356] Deal with prior EH/abormal cleanup when fixing up noreturn calls

[Richard Biener]

https://gcc.gnu.org/g:732c0a78740860340c58f32bab5bf215d9032007

commit r15-10356-g732c0a78740860340c58f32bab5bf215d9032007
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Sep 10 17:14:07 2025 +0200

    Deal with prior EH/abormal cleanup when fixing up noreturn calls
    
    When a dead EH or abnormal edge makes a call queued for noreturn fixup
    unreachable, just skip processing it.
    
            PR tree-optimization/121870
            * tree-ssa-propagate.cc
            (substitute_and_fold_engine::substitute_and_fold): Skip
            removed stmts from noreturn fixup.
    
            * g++.dg/torture/pr121870.C: New testcase.
    
    (cherry picked from commit 5c4f1313e753aeb6920a48c62c7c99ad36e1adae)

Diff:
---
 gcc/testsuite/g++.dg/torture/pr121870.C | 20 ++++++++++++++++++++
 gcc/tree-ssa-propagate.cc               |  2 ++
 2 files changed, 22 insertions(+)

diff --git a/gcc/testsuite/g++.dg/torture/pr121870.C b/gcc/testsuite/g++.dg/torture/pr121870.C
new file mode 100644
index 000000000000..8f4e7ab50696
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr121870.C
@@ -0,0 +1,20 @@
+__attribute__((noreturn)) void f1(void)
+{
+    while(true) {}
+}
+static void (*fptr)(void) = f1;
+struct s1
+{
+    ~s1() {
+        fptr();
+    }
+    void DoInner() {
+        fptr();
+    }
+};
+
+void f()
+{
+    s1 xxx;
+    xxx.DoInner();
+}
diff --git a/gcc/tree-ssa-propagate.cc b/gcc/tree-ssa-propagate.cc
index ec2068948215..872f881b644c 100644
--- a/gcc/tree-ssa-propagate.cc
+++ b/gcc/tree-ssa-propagate.cc
@@ -1019,6 +1019,8 @@ substitute_and_fold_engine::substitute_and_fold (basic_block block)
   while (!walker.stmts_to_fixup.is_empty ())
     {
       gimple *stmt = walker.stmts_to_fixup.pop ();
+      if (!gimple_bb (stmt))
+	continue;
       if (dump_file && dump_flags & TDF_DETAILS)
 	{
 	  fprintf (dump_file, "Fixing up noreturn call ");