PR16054: Slight strengthening for -Wsometimes-uninitialized: if we use a

variable uninitialized every time we reach its (reachable) declaration, or
every time we call the surrounding function, promote the warning from
-Wmaybe-uninitialized to -Wsometimes-uninitialized.

This is still slightly weaker than desired: we should, in general, warn
if a use is uninitialized the first time it is evaluated.

llvm-svn: 190623

1 files changed, 50 insertions, 8 deletions

diff --git a/clang/test/Analysis/uninit-sometimes.cpp b/clang/test/Analysis/uninit-sometimes.cpp
index 015b675d9b8..425d3048c4e 100644
--- a/clang/test/Analysis/uninit-sometimes.cpp
+++ b/clang/test/Analysis/uninit-sometimes.cpp
@@ -145,13 +145,13 @@ int test_for_range_false(int k) {
 
 int test_for_range_true(int k) {
   int arr[3] = { 1, 2, 3 };
-  int x;
-  for (int &a : arr) { // no-warning
+  int x; // expected-note {{variable}}
+  for (int &a : arr) { // expected-warning {{variable 'x' is used uninitialized whenever 'for' loop is entered}}
     goto label;
   }
   x = 0;
 label:
-  return x;
+  return x; // expected-note {{uninitialized use}}
 }
 
 
@@ -356,14 +356,14 @@ int test_no_false_positive_2() {
 }
 
 
-// FIXME: In this case, the variable is used uninitialized whenever the
-// function's entry block is reached. Produce a diagnostic saying that
-// the variable is uninitialized the first time it is used.
+
+
+
 void test_null_pred_succ() {
-  int x;
+  int x; // expected-note {{variable}} expected-warning {{used uninitialized whenever function 'test_null_pred_succ' is called}}
   if (0)
     foo: x = 0;
-  if (x)
+  if (x) // expected-note {{use}}
     goto foo;
 }
 
@@ -385,3 +385,45 @@ int PR13360(bool b) {
 
 // CHECK: fix-it:"{{.*}}":{376:3-380:10}:""
 // CHECK: fix-it:"{{.*}}":{375:8-375:8}:" = 0"
+
+void test_jump_init() {
+goto later;
+  int x; // expected-note {{variable}} expected-warning {{used uninitialized whenever function 'test_jump_init'}}
+later:
+  while (x) x = 0; // expected-note {{use}}
+}
+
+void PR16054() {
+  int x; // expected-note {{variable}} expected-warning {{used uninitialized whenever function 'PR16054}}
+  while (x != 0) { // expected-note {{use}}
+    (void)&x;
+  }
+}
+
+void test_loop_uninit() {
+  for (int n = 0; n < 10; ++n) {
+    int k; // expected-warning {{variable 'k' is used uninitialized whenever its declaration is reached}} expected-note {{variable}}
+    do {
+      k = k + 1; // expected-note {{use}}
+    } while (k != 5);
+  }
+}
+
+// FIXME: We should warn here, because the variable is used uninitialized
+// the first time we encounter the use.
+void test_loop_with_assignment() {
+  double d;
+  for (int n = 0; n < 10; ++n) {
+    d = d + n;
+  }
+}
+
+// FIXME: We should warn here, because the variable is used uninitialized
+// the first time we encounter the use.
+void test_loop_with_ref_bind() {
+  double d;
+  for (int n = 0; n < 10; ++n) {
+    d += n;
+    const double &r = d;
+  }
+}