-Wuninitialized: assume that an __attribute__((returns_twice)) function might

initialize any variable. This is extremely conservative, but is sufficient for
now.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159620 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 19 insertions, 0 deletions

diff --git a/test/Sema/uninit-variables.c b/test/Sema/uninit-variables.c
index 59577b9585..71ce76c3e3 100644
--- a/test/Sema/uninit-variables.c
+++ b/test/Sema/uninit-variables.c
@@ -466,3 +466,22 @@ skip_decl:
     k = produce();
   }
 }
+
+typedef char jmp_buf[256];
+extern int setjmp(jmp_buf env); // implicitly returns_twice
+
+void do_stuff_and_longjmp(jmp_buf env, int *result) __attribute__((noreturn));
+
+int returns_twice() {
+  int a; // expected-note {{initialize}}
+  if (!a) { // expected-warning {{variable 'a' is uninitialized}}
+    jmp_buf env;
+    int b;
+    if (setjmp(env) == 0) {
+      do_stuff_and_longjmp(env, &b);
+    } else {
+      a = b; // no warning
+    }
+  }
+  return a;
+}