[clang] [SSAF][PointerFlowExtractor] Handle empty initializer lists for scalars and unions (PR #201968)

[Balázs Benics via cfe-commits]

================
@@ -967,6 +967,53 @@ TEST_F(PointerFlowTest, ArrayOfStructInitList) {
                                       }));
 }
 
+TEST_F(PointerFlowTest, ScalarPointerBraceInit) {
+  ASSERT_EQ(setUpTest(R"cpp(
+    int *q;
+    void foo() {
+      int *p{q};
+    }
+  )cpp"),
+            true);
+
+  auto *Sum = getEntitySummary("foo");
+
+  ASSERT_NE(Sum, nullptr);
+  EXPECT_EQ(*Sum, makeEdges(__LINE__, {{{"p", 1U}, {"q", 1U}}}));
+}
+
+TEST_F(PointerFlowTest, EmptyInitsScalarInt) {
+  ASSERT_EQ(setUpTest(R"cpp(
+    void foo() {
+      int x{};
+      int y = {};
+      int *p{};
+      int *q = {};
+    }
+  )cpp"),
+            true);
+
+  auto *Sum = getEntitySummary("foo");
+
+  // No pointer-flow edge for 0-initialized scalar.
+  ASSERT_EQ(Sum, nullptr);
+}
+
+TEST_F(PointerFlowTest, EmptyInitsUnion) {
+  ASSERT_EQ(setUpTest(R"cpp(
+    union U { int x; int *p; };
+    void foo() {
+      U u{};
+      U uu = {};
+    }
+  )cpp"),
+            true);
+
+  auto *Sum = getEntitySummary("foo");
+
+  ASSERT_EQ(Sum, nullptr);
+}
----------------
steakhal wrote:

Could you also demonstrate this empty init for structs and classes?

https://github.com/llvm/llvm-project/pull/201968