[gcc r11-7932] PR middle-end/65182 - -Wuninitialized fails when pointer to variable later passed to function

[Martin Sebor]

https://gcc.gnu.org/g:31199d95de1304e200554bbf98b2d8a6a7298bec

commit r11-7932-g31199d95de1304e200554bbf98b2d8a6a7298bec
Author: Martin Sebor <msebor@redhat.com>
Date:   Wed Mar 31 10:39:24 2021 -0600

    PR middle-end/65182 - -Wuninitialized fails when pointer to variable later passed to function
    
    gcc/testsuite:
            PR middle-end/65182
            * gcc.dg/uninit-pr65182.c: New test.

Diff:
---
 gcc/testsuite/gcc.dg/uninit-pr65182.c | 44 +++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/gcc/testsuite/gcc.dg/uninit-pr65182.c b/gcc/testsuite/gcc.dg/uninit-pr65182.c
new file mode 100644
index 00000000000..45b538d1a2f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/uninit-pr65182.c
@@ -0,0 +1,44 @@
+/* PR middle-end/65182 - -Wuninitialized fails when pointer to variable
+   later passed to function
+   { dg-do compile }
+   { dg-options "-O0 -Wall" } */
+
+void bar (int *a);
+
+int baz (void);
+
+__attribute__ ((noipa)) void foo_O0 (int *b)
+{
+  int a;
+
+  if (a)            // { dg-warning "\\\[-Wuninitialized" }
+    {
+      *b = 0;
+      return;
+    }
+
+  bar (&a);
+
+  a = baz ();
+
+  *b = a + 2;
+}
+
+#pragma GCC optimize ("2")
+
+__attribute__ ((noipa)) void foo_O2 (int *b)
+{
+  int a;
+
+  if (a)            // { dg-warning "\\\[-Wuninitialized" }
+    {
+      *b = 0;
+      return;
+    }
+
+  bar (&a);
+
+  a = baz ();
+
+  *b = a + 3;
+}