1 files changed, 94 insertions, 5 deletions

diff --git a/clang/test/Analysis/inlining/false-positive-suppression.c b/clang/test/Analysis/inlining/false-positive-suppression.c
index be485e0c1c6..20cc3114875 100644
--- a/clang/test/Analysis/inlining/false-positive-suppression.c
+++ b/clang/test/Analysis/inlining/false-positive-suppression.c
@@ -1,9 +1,14 @@
 // RUN: %clang_cc1 -analyze -analyzer-checker=core -analyzer-config suppress-null-return-paths=false -verify %s
-// RUN: %clang_cc1 -analyze -analyzer-checker=core -verify -DSUPPRESSED %s
+// RUN: %clang_cc1 -analyze -analyzer-checker=core -verify -DSUPPRESSED=1 %s
+// RUN: %clang_cc1 -analyze -analyzer-checker=core -analyzer-config avoid-suppressing-null-argument-paths=true -DSUPPRESSED=1 -DNULL_ARGS=1 -verify %s
 
 int opaquePropertyCheck(void *object);
 int coin();
 
+int *getNull() {
+  return 0;
+}
+
 int *dynCastToInt(void *ptr) {
   if (opaquePropertyCheck(ptr))
     return (int *)ptr;
@@ -69,24 +74,108 @@ void testBranchReversed(void *p) {
 }
 
 
+// --------------------------
+// "Suppression suppression"
+// --------------------------
+
+void testDynCastOrNullOfNull() {
+  // Don't suppress when one of the arguments is NULL.
+  int *casted = dynCastOrNull(0);
+  *casted = 1;
+#if !SUPPRESSED || NULL_ARGS
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+void testDynCastOfNull() {
+  // Don't suppress when one of the arguments is NULL.
+  int *casted = dynCastToInt(0);
+  *casted = 1;
+#if !SUPPRESSED || NULL_ARGS
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+int *lookUpInt(int unused) {
+  if (coin())
+    return 0;
+  static int x;
+  return &x;
+}
+
+void testZeroIsNotNull() {
+  // /Do/ suppress when the argument is 0 (an integer).
+  int *casted = lookUpInt(0);
+  *casted = 1;
+#ifndef SUPPRESSED
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+void testTrackNull() {
+  // /Do/ suppress if the null argument came from another call returning null.
+  int *casted = dynCastOrNull(getNull());
+  *casted = 1;
+#ifndef SUPPRESSED
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+void testTrackNullVariable() {
+  // /Do/ suppress if the null argument came from another call returning null.
+  int *ptr;
+  ptr = getNull();
+  int *casted = dynCastOrNull(ptr);
+  *casted = 1;
+#ifndef SUPPRESSED
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+
 // ---------------------------------------
 // FALSE NEGATIVES (over-suppression)
 // ---------------------------------------
 
-void testDynCastOrNullOfNull() {
+void testNoArguments() {
+  // In this case the function has no branches, and MUST return null.
+  int *casted = getNull();
+  *casted = 1;
+#ifndef SUPPRESSED
+  // expected-warning@-2 {{Dereference of null pointer}}
+#endif
+}
+
+int *getNullIfNonNull(void *input) {
+  if (input)
+    return 0;
+  static int x;
+  return &x;
+}
+
+void testKnownPath(void *input) {
+  if (!input)
+    return;
+
   // In this case we have a known value for the argument, and thus the path
   // through the function doesn't ever split.
-  int *casted = dynCastOrNull(0);
+  int *casted = getNullIfNonNull(input);
   *casted = 1;
 #ifndef SUPPRESSED
   // expected-warning@-2 {{Dereference of null pointer}}
 #endif
 }
 
-void testDynCastOfNull() {
+int *alwaysReturnNull(void *input) {
+  if (opaquePropertyCheck(input))
+    return 0;
+  return 0;
+}
+
+void testAlwaysReturnNull(void *input) {
   // In this case all paths out of the function return 0, but they are all
   // dominated by a branch whose condition we don't know!
-  int *casted = dynCastToInt(0);
+  int *casted = alwaysReturnNull(input);
   *casted = 1;
 #ifndef SUPPRESSED
   // expected-warning@-2 {{Dereference of null pointer}}