[analyzer] MallocSizeofChecker false positive: when sizeof is argument
to addition.
We should not to warn in case the malloc size argument is an
addition containing 'sizeof' operator - it is common to use the pattern
to pack values of different sizes into a buffer.
Ex:
uint8_t *buffer = (uint8_t*)malloc(dataSize + sizeof(length));
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158219 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/MallocSizeofChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocSizeofChecker.cpp
index 46b3500..6292a47 100644
--- a/lib/StaticAnalyzer/Checkers/MallocSizeofChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocSizeofChecker.cpp
@@ -118,11 +118,6 @@
Visit(E->getRHS());
}
- void VisitBinAdd(const BinaryOperator *E) {
- Visit(E->getLHS());
- Visit(E->getRHS());
- }
-
void VisitImplicitCastExpr(const ImplicitCastExpr *E) {
return Visit(E->getSubExpr());
}
diff --git a/test/Analysis/malloc-sizeof.c b/test/Analysis/malloc-sizeof.c
index af8600a..6eb466a 100644
--- a/test/Analysis/malloc-sizeof.c
+++ b/test/Analysis/malloc-sizeof.c
@@ -10,13 +10,14 @@
struct A {};
struct B {};
-void foo() {
+void foo(unsigned int unsignedInt, unsigned int readSize) {
int *ip1 = malloc(sizeof(1));
int *ip2 = malloc(4 * sizeof(int));
long *lp1 = malloc(sizeof(short)); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'long', which is incompatible with sizeof operand type 'short'}}
long *lp2 = malloc(5 * sizeof(double)); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'long', which is incompatible with sizeof operand type 'double'}}
- long *lp3 = malloc(5 * sizeof(char) + 2); // expected-warning {{Result of 'malloc' is converted to a pointer of type 'long', which is incompatible with sizeof operand type 'char'}}
+ char *cp3 = malloc(5 * sizeof(char) + 2); // no warning
+ unsigned char *buf = malloc(readSize + sizeof(unsignedInt)); // no warning
struct A *ap1 = calloc(1, sizeof(struct A));
struct A *ap2 = calloc(2, sizeof(*ap1));
