[gcc r13-9506] testsuite: add testcase for fixed PR107467

[Richard Biener via Gcc-cvs]

https://gcc.gnu.org/g:35aede5a6bc9b2cf7e7d019148debb6f227c6eb1

commit r13-9506-g35aede5a6bc9b2cf7e7d019148debb6f227c6eb1
Author: Sam James <s...@gentoo.org>
Date:   Mon Oct 21 12:11:42 2024 +0100

    testsuite: add testcase for fixed PR107467
    
    PR107467 ended up being fixed by the fix for PR115110, but let's
    add the testcase on top.
    
    gcc/testsuite/ChangeLog:
            PR tree-optimization/107467
            PR middle-end/115110
    
            * g++.dg/lto/pr107467_0.C: New test.
    
    (cherry picked from commit 4e09ae37dbe0a10f48490214f50ff733cc92280a)

Diff:
---
 gcc/testsuite/g++.dg/lto/pr107467_0.C | 52 +++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/gcc/testsuite/g++.dg/lto/pr107467_0.C 
b/gcc/testsuite/g++.dg/lto/pr107467_0.C
new file mode 100644
index 000000000000..a871aca82459
--- /dev/null
+++ b/gcc/testsuite/g++.dg/lto/pr107467_0.C
@@ -0,0 +1,52 @@
+/* { dg-lto-do run } */
+/* { dg-lto-options {{ -O2 -fno-strict-aliasing -flto }} } */
+
+template <class T>
+struct pair
+{
+    int first;
+    T second;
+};
+
+template <typename C>
+[[gnu::optimize("strict-aliasing")]]
+bool __attribute__((noinline))
+compare_pairs(const pair<C> &lhs, const pair<C> &rhs) {
+  return lhs.first == rhs.first && lhs.second == rhs.second;
+}
+
+template <typename B> struct Combined {
+  pair<B *> 
+__attribute__((noinline)) get_const() {
+    return pair<B *>{123, nullptr};
+  }
+[[gnu::optimize("strict-aliasing")]]
+  bool 
+__attribute__((noinline)) clashy() {
+    return compare_pairs(get_const(), get_const());
+  }
+};
+
+class SomeClass {};
+class OtherClass {};
+
+[[gnu::optimize("strict-aliasing")]]
+[[gnu::used]]
+void some_func() {
+  Combined<SomeClass> myvar;
+  __builtin_printf("%i\n", myvar.clashy());
+}
+
+[[gnu::optimize("strict-aliasing")]]
+void other_func() {
+  Combined<OtherClass> myvar;
+  int t = myvar.clashy();
+  if (!t)
+  __builtin_abort();
+}
+
+[[gnu::optimize("O0")]]
+int main()
+{
+  other_func();
+}