Author: arphaman Date: Wed Nov 23 10:57:03 2016 New Revision: 287776 URL: http://llvm.org/viewvc/llvm-project?rev=287776&view=rev Log: [Sema][Atomics] Treat expected pointer in compare exchange atomics as _Nonnull
This commit teaches clang that is has to emit a warning when NULL is passed as the 'expected' pointer parameter into an atomic compare exchange call. rdar://18926650 Differential Revision: https://reviews.llvm.org/D26978 Modified: cfe/trunk/lib/Sema/SemaChecking.cpp cfe/trunk/test/Sema/atomic-ops.c Modified: cfe/trunk/lib/Sema/SemaChecking.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=287776&r1=287775&r2=287776&view=diff ============================================================================== --- cfe/trunk/lib/Sema/SemaChecking.cpp (original) +++ cfe/trunk/lib/Sema/SemaChecking.cpp Wed Nov 23 10:57:03 2016 @@ -2868,6 +2868,9 @@ ExprResult Sema::SemaAtomicOpsOverloaded Ty = Context.getPointerDiffType(); else { Expr *ValArg = TheCall->getArg(i); + // Treat this argument as _Nonnull as we want to show a warning if + // NULL is passed into it. + CheckNonNullArgument(*this, ValArg, DRE->getLocStart()); unsigned AS = 0; // Keep address space of non-atomic pointer type. if (const PointerType *PtrTy = Modified: cfe/trunk/test/Sema/atomic-ops.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/atomic-ops.c?rev=287776&r1=287775&r2=287776&view=diff ============================================================================== --- cfe/trunk/test/Sema/atomic-ops.c (original) +++ cfe/trunk/test/Sema/atomic-ops.c Wed Nov 23 10:57:03 2016 @@ -174,14 +174,14 @@ void f(_Atomic(int) *i, const _Atomic(in __atomic_fetch_or(D, 3, memory_order_seq_cst); // expected-error {{must be a pointer to integer}} __atomic_fetch_and(s1, 3, memory_order_seq_cst); // expected-error {{must be a pointer to integer}} - _Bool cmpexch_1 = __c11_atomic_compare_exchange_strong(i, 0, 1, memory_order_seq_cst, memory_order_seq_cst); - _Bool cmpexch_2 = __c11_atomic_compare_exchange_strong(p, 0, (int*)1, memory_order_seq_cst, memory_order_seq_cst); - _Bool cmpexch_3 = __c11_atomic_compare_exchange_strong(d, (int*)0, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{incompatible pointer types}} + _Bool cmpexch_1 = __c11_atomic_compare_exchange_strong(i, I, 1, memory_order_seq_cst, memory_order_seq_cst); + _Bool cmpexch_2 = __c11_atomic_compare_exchange_strong(p, P, (int*)1, memory_order_seq_cst, memory_order_seq_cst); + _Bool cmpexch_3 = __c11_atomic_compare_exchange_strong(d, I, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{incompatible pointer types}} (void)__c11_atomic_compare_exchange_strong(i, CI, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{passing 'const int *' to parameter of type 'int *' discards qualifiers}} - _Bool cmpexchw_1 = __c11_atomic_compare_exchange_weak(i, 0, 1, memory_order_seq_cst, memory_order_seq_cst); - _Bool cmpexchw_2 = __c11_atomic_compare_exchange_weak(p, 0, (int*)1, memory_order_seq_cst, memory_order_seq_cst); - _Bool cmpexchw_3 = __c11_atomic_compare_exchange_weak(d, (int*)0, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{incompatible pointer types}} + _Bool cmpexchw_1 = __c11_atomic_compare_exchange_weak(i, I, 1, memory_order_seq_cst, memory_order_seq_cst); + _Bool cmpexchw_2 = __c11_atomic_compare_exchange_weak(p, P, (int*)1, memory_order_seq_cst, memory_order_seq_cst); + _Bool cmpexchw_3 = __c11_atomic_compare_exchange_weak(d, I, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{incompatible pointer types}} (void)__c11_atomic_compare_exchange_weak(i, CI, 1, memory_order_seq_cst, memory_order_seq_cst); // expected-warning {{passing 'const int *' to parameter of type 'int *' discards qualifiers}} _Bool cmpexch_4 = __atomic_compare_exchange_n(I, I, 5, 1, memory_order_seq_cst, memory_order_seq_cst); @@ -503,4 +503,9 @@ void memory_checks(_Atomic(int) *Ap, int (void)__atomic_compare_exchange_n(p, p, val, 0, memory_order_seq_cst, memory_order_relaxed); } - +void nullPointerWarning(_Atomic(int) *Ap, int *p, int val) { + // The 'expected' pointer shouldn't be NULL. + (void)__c11_atomic_compare_exchange_strong(Ap, NULL, val, memory_order_relaxed, memory_order_relaxed); // expected-warning {{null passed to a callee that requires a non-null argument}} + (void)atomic_compare_exchange_weak(Ap, ((void*)0), val); // expected-warning {{null passed to a callee that requires a non-null argument}} + (void)__atomic_compare_exchange_n(p, NULL, val, 0, memory_order_relaxed, memory_order_relaxed); // expected-warning {{null passed to a callee that requires a non-null argument}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits