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// RUN: %clang_analyze_cc1 -analyzer-checker=core,osx.coreFoundation.CFRetainRelease,osx.cocoa.RetainCount -verify %s
#pragma clang arc_cf_code_audited begin
typedef const void * CFTypeRef;
extern CFTypeRef CFRetain(CFTypeRef cf);
extern void CFRelease(CFTypeRef cf);
#pragma clang arc_cf_code_audited end
#define CF_RETURNS_RETAINED __attribute__((cf_returns_retained))
#define CF_CONSUMED __attribute__((cf_consumed))
extern CFTypeRef CFCreate() CF_RETURNS_RETAINED;
// A "safe" variant of CFRetain that doesn't crash when a null pointer is
// retained. This is often defined by users in a similar manner. The
// CF_RETURNS_RETAINED annotation is misleading here, because the function
// is not supposed to return an object with a +1 retain count. Instead, it
// is supposed to return an object with +(N+1) retain count, where N is
// the original retain count of 'cf'. However, there is no good annotation
// to use in this case, and it is pointless to provide such annotation
// because the only use cases would be CFRetain and SafeCFRetain.
// So instead we teach the analyzer to be able to accept such code
// and ignore the misplaced annotation.
CFTypeRef SafeCFRetain(CFTypeRef cf) CF_RETURNS_RETAINED {
if (cf) {
return CFRetain(cf);
}
return cf;
}
// A "safe" variant of CFRelease that doesn't crash when a null pointer is
// released. The CF_CONSUMED annotation seems reasonable here.
void SafeCFRelease(CFTypeRef CF_CONSUMED cf) {
if (cf)
CFRelease(cf); // no-warning (when inlined)
}
void escape(CFTypeRef cf);
void makeSureTestsWork() {
CFTypeRef cf = CFCreate();
CFRelease(cf);
CFRelease(cf); // expected-warning{{Reference-counted object is used after it is released}}
}
// Make sure we understand that the second SafeCFRetain doesn't return an
// object with +1 retain count, which we won't be able to release twice.
void falseOverrelease(CFTypeRef cf) {
SafeCFRetain(cf);
SafeCFRetain(cf);
SafeCFRelease(cf);
SafeCFRelease(cf); // no-warning after inlining this.
}
// Regular CFRelease() should behave similarly.
void sameWithNormalRelease(CFTypeRef cf) {
SafeCFRetain(cf);
SafeCFRetain(cf);
CFRelease(cf);
CFRelease(cf); // no-warning
}
// Make sure we understand that the second SafeCFRetain doesn't return an
// object with +1 retain count, which would no longer be owned by us after
// it escapes to escape() and released once.
void falseReleaseNotOwned(CFTypeRef cf) {
SafeCFRetain(cf);
SafeCFRetain(cf);
escape(cf);
SafeCFRelease(cf);
SafeCFRelease(cf); // no-warning after inlining this.
}
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