[Bug tree-optimization/119614] [15 regression] protobuf-29.4 fails to build with -O2 (error: cannot tail-call: call and return value are different)

[jakub at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119614

--- Comment #20 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
--- gcc/testsuite/g++.dg/lto/pr119614_0.C.jj    2025-04-07 08:44:32.868051786
+0200
+++ gcc/testsuite/g++.dg/lto/pr119614_0.C       2025-04-07 08:44:27.810122315
+0200
@@ -0,0 +1,34 @@
+// PR tree-optimization/119614
+// { dg-lto-do link }
+// { dg-lto-options { { -O2 -fPIC -flto -flto-partition=max } } }
+// { dg-require-effective-target shared }
+// { dg-require-effective-target fpic }
+// { dg-require-effective-target musttail }
+// { dg-extra-ld-options "-shared" }
+
+struct S {} b;
+char *foo ();
+int e, g;
+void bar ();
+void corge (S);
+
+[[gnu::noinline]] static char *
+baz ()
+{
+  bar ();
+  return 0;
+}
+
+const char *
+qux ()
+{
+  if (e)
+    {
+      S a = b;
+      corge (a);
+      if (g)
+        return 0;
+      [[gnu::musttail]] return baz ();
+    }
+  return foo ();
+}