llvm-project/clang/test/Analysis/inlining/false-positive-suppression.c

367 lines
8.8 KiB
C

// 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=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* getPtr();
int *dynCastToInt(void *ptr) {
if (opaquePropertyCheck(ptr))
return (int *)ptr;
return 0;
}
int *dynCastOrNull(void *ptr) {
if (!ptr)
return 0;
if (opaquePropertyCheck(ptr))
return (int *)ptr;
return 0;
}
void testDynCast(void *p) {
int *casted = dynCastToInt(p);
*casted = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void testDynCastOrNull(void *p) {
int *casted = dynCastOrNull(p);
*casted = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void testBranch(void *p) {
int *casted;
// Although the report will be suppressed on one branch, it should still be
// valid on the other.
if (coin()) {
casted = dynCastToInt(p);
} else {
if (p)
return;
casted = (int *)p;
}
*casted = 1; // expected-warning {{Dereference of null pointer}}
}
void testBranchReversed(void *p) {
int *casted;
// Although the report will be suppressed on one branch, it should still be
// valid on the other.
if (coin()) {
if (p)
return;
casted = (int *)p;
} else {
casted = dynCastToInt(p);
}
*casted = 1; // expected-warning {{Dereference of null pointer}}
}
void testMultipleStore(void *p) {
int *casted = 0;
casted = dynCastToInt(p);
*casted = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
// Test that div by zero does not get suppressed. This is a policy choice.
int retZero() {
return 0;
}
int triggerDivZero () {
int y = retZero();
return 5/y; // expected-warning {{Division by zero}}
}
// Treat a function-like macro similarly to an inlined function, so suppress
// warnings along paths resulting from inlined checks.
#define MACRO_WITH_CHECK(a) ( ((a) != 0) ? *a : 17)
void testInlineCheckInMacro(int *p) {
int i = MACRO_WITH_CHECK(p);
(void)i;
*p = 1; // no-warning
}
#define MACRO_WITH_NESTED_CHECK(a) ( { int j = MACRO_WITH_CHECK(a); j; } )
void testInlineCheckInNestedMacro(int *p) {
int i = MACRO_WITH_NESTED_CHECK(p);
(void)i;
*p = 1; // no-warning
}
// If there is a check in a macro that is not function-like, don't treat
// it like a function so don't suppress.
#define NON_FUNCTION_MACRO_WITH_CHECK ( ((p) != 0) ? *p : 17)
void testNonFunctionMacro(int *p) {
int i = NON_FUNCTION_MACRO_WITH_CHECK ;
(void)i;
*p = 1; // expected-warning {{Dereference of null pointer (loaded from variable 'p')}}
}
// This macro will dereference its argument if the argument is NULL.
#define MACRO_WITH_ERROR(a) ( ((a) != 0) ? 0 : *a)
void testErrorInMacro(int *p) {
int i = MACRO_WITH_ERROR(p); // expected-warning {{Dereference of null pointer (loaded from variable 'p')}}
(void)i;
}
// Here the check (the "if") is not in a macro, so we should still warn.
#define MACRO_IN_GUARD(a) (!(a))
void testMacroUsedAsGuard(int *p) {
if (MACRO_IN_GUARD(p))
*p = 1; // expected-warning {{Dereference of null pointer (loaded from variable 'p')}}
}
// When a nil case split is introduced in a macro and the macro is in a guard,
// we still shouldn't warn.
int isNull(int *p);
int isEqual(int *p, int *q);
#define ISNULL(ptr) ((ptr) == 0 || isNull(ptr))
#define ISEQUAL(a, b) ((int *)(a) == (int *)(b) || (ISNULL(a) && ISNULL(b)) || isEqual(a,b))
#define ISNOTEQUAL(a, b) (!ISEQUAL(a, b))
void testNestedDisjunctiveMacro(int *p, int *q) {
if (ISNOTEQUAL(p,q)) {
(void)*p; // no-warning
(void)*q; // no-warning
}
(void)*p; // no-warning
(void)*q; // no-warning
}
// Here the check is entirely in non-macro code even though the code itself
// is a macro argument.
#define MACRO_DO_IT(a) (a)
void testErrorInArgument(int *p) {
int i = MACRO_DO_IT((p ? 0 : *p)); // expected-warning {{Dereference of null pointer (loaded from variable 'p')}}c
(void)i;
}
// --------------------------
// "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
}
void inlinedIsDifferent(int inlined) {
int i;
// We were erroneously picking up the inner stack frame's initialization,
// even though the error occurs in the outer stack frame!
int *p = inlined ? &i : getNull();
if (!inlined)
inlinedIsDifferent(1);
*p = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void testInlinedIsDifferent() {
// <rdar://problem/13787723>
inlinedIsDifferent(0);
}
// ---------------------------------------
// FALSE NEGATIVES (over-suppression)
// ---------------------------------------
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 = getNullIfNonNull(input);
*casted = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
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 = alwaysReturnNull(input);
*casted = 1;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
int derefArg(int *p) {
return *p;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void ternaryArg(char cond) {
static int x;
derefArg(cond ? &x : getNull());
}
int derefArgCast(char *p) {
return *p;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void ternaryArgCast(char cond) {
static int x;
derefArgCast((char*)((unsigned)cond ? &x : getNull()));
}
int derefAssignment(int *p) {
return *p;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
void ternaryAssignment(char cond) {
static int x;
int *p = cond ? getNull() : getPtr();
derefAssignment(p);
}
int *retNull(char cond) {
static int x;
return cond ? &x : getNull();
}
int ternaryRetNull(char cond) {
int *p = retNull(cond);
return *p;
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
// Test suppression of nested conditional operators.
int testConditionalOperatorSuppress(int x) {
return *(x ? getNull() : getPtr());
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
int testNestedConditionalOperatorSuppress(int x) {
return *(x ? (x ? getNull() : getPtr()) : getPtr());
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}
int testConditionalOperator(int x) {
return *(x ? 0 : getPtr()); // expected-warning {{Dereference of null pointer}}
}
int testNestedConditionalOperator(int x) {
return *(x ? (x ? 0 : getPtr()) : getPtr()); // expected-warning {{Dereference of null pointer}}
}
int testConditionalOperatorSuppressFloatCond(float x) {
return *(x ? getNull() : getPtr());
#ifndef SUPPRESSED
// expected-warning@-2 {{Dereference of null pointer}}
#endif
}