Enhance dead store checker to not flag preincrements to dead variables where the preincrement is a subexpression, e.g. foo(++x); This can cause false negatives, but will remove a whole class of false positives.

llvm-svn: 57554

1 files changed, 7 insertions, 1 deletions

diff --git a/clang/test/Analysis/dead-stores.c b/clang/test/Analysis/dead-stores.c
index 2a67afd0b0f..71c4e3b28bf 100644
--- a/clang/test/Analysis/dead-stores.c
+++ b/clang/test/Analysis/dead-stores.c
@@ -74,9 +74,15 @@ int f10() {
 
 int f11() {
   int x = 4;
-  return ++x; // expected-warning{{never read}}
+  return x++; // expected-warning{{never read}}
 }
 
+int f11b() {
+  int x = 4;
+  return ++x; // no-warning
+}
+
+
 int f12a(int y) {
   int x = y;  // expected-warning{{never read}}
   return 1;