retain-count-alloc.cpp
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// RUN: %clang_analyze_cc1 \
// RUN: -analyzer-checker=core,unix.Malloc \
// RUN: -verify %s
// expected-no-diagnostics: We do not model Integer Set Library's retain-count
// based allocation. If any of the parameters has an
// '__isl_' prefixed macro definition we escape every
// of them when we are about to 'free()' something.
#define __isl_take
#define __isl_keep
struct Object { int Ref; };
void free(void *);
Object *copyObj(__isl_keep Object *O) {
O->Ref++;
return O;
}
void freeObj(__isl_take Object *O) {
if (--O->Ref > 0)
return;
free(O); // Here we notice that the parameter contains '__isl_', escape it.
}
void useAfterFree(__isl_take Object *A) {
if (!A)
return;
Object *B = copyObj(A);
freeObj(B);
A->Ref = 13;
// no-warning: 'Use of memory after it is freed' was here.
}