diff options
Diffstat (limited to 'clang/test/Analysis')
| -rw-r--r-- | clang/test/Analysis/analyzer-enabled-checkers.c | 1 | ||||
| -rw-r--r-- | clang/test/Analysis/placement-new.cpp | 32 | ||||
| -rw-r--r-- | clang/test/Analysis/std-c-library-functions-arg-enabled-checkers.c | 1 |
3 files changed, 26 insertions, 8 deletions
diff --git a/clang/test/Analysis/analyzer-enabled-checkers.c b/clang/test/Analysis/analyzer-enabled-checkers.c index a632b70..32afcf3 100644 --- a/clang/test/Analysis/analyzer-enabled-checkers.c +++ b/clang/test/Analysis/analyzer-enabled-checkers.c @@ -20,7 +20,6 @@ // CHECK-NEXT: core.NonNullParamChecker // CHECK-NEXT: core.NonnilStringConstants // CHECK-NEXT: core.NullDereference -// CHECK-NEXT: core.StackAddrEscapeBase // CHECK-NEXT: core.StackAddressEscape // CHECK-NEXT: core.UndefinedBinaryOperatorResult // CHECK-NEXT: core.VLASize diff --git a/clang/test/Analysis/placement-new.cpp b/clang/test/Analysis/placement-new.cpp index 766b11c..50bbde2 100644 --- a/clang/test/Analysis/placement-new.cpp +++ b/clang/test/Analysis/placement-new.cpp @@ -166,10 +166,29 @@ void f1() { short a; }; - // bad (not enough space). + // On some systems, (notably before MSVC 16.7), a non-allocating placement + // array new could allocate more memory than the nominal size of the array. + + // Since CWG 2382 (implemented in MSVC 16.7), overhead was disallowed for non-allocating placement new. + // See: + // https://learn.microsoft.com/en-us/cpp/overview/visual-cpp-language-conformance?view=msvc-170 + // https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1969r0.html#2382 + + // However, as of 17.1, there is a regression when the type comes from a template + // parameter where MSVC reintroduces overhead. + // See: + // https://developercommunity.visualstudio.com/t/10777485 + // https://godbolt.org/z/E1z1Tsfvj + + // The checker doesn't warn here because this behavior only affects older + // MSVC versions (<16.7) or certain specific versions (17.1). + // Suppressing warnings avoids false positives on standard-compliant compilers + // and modern MSVC versions, but users of affected MSVC versions should be + // aware of potential buffer size issues. + const unsigned N = 32; - alignas(S) unsigned char buffer1[sizeof(S) * N]; // expected-note {{'buffer1' initialized here}} - ::new (buffer1) S[N]; // expected-warning{{Storage provided to placement new is only 64 bytes, whereas the allocated array type requires more space for internal needs}} expected-note 1 {{}} + alignas(S) unsigned char buffer1[sizeof(S) * N]; + ::new (buffer1) S[N]; // no-warning: See comments above } void f2() { @@ -177,10 +196,11 @@ void f2() { short a; }; - // maybe ok but we need to warn. + // On some systems, placement array new could allocate more memory than the nominal size of the array. + // See the comment at f1() above for more details. const unsigned N = 32; - alignas(S) unsigned char buffer2[sizeof(S) * N + sizeof(int)]; // expected-note {{'buffer2' initialized here}} - ::new (buffer2) S[N]; // expected-warning{{68 bytes is possibly not enough for array allocation which requires 64 bytes. Current overhead requires the size of 4 bytes}} expected-note 1 {{}} + alignas(S) unsigned char buffer2[sizeof(S) * N + sizeof(int)]; + ::new (buffer2) S[N]; // no-warning: See comments above } } // namespace testArrayTypesAllocation diff --git a/clang/test/Analysis/std-c-library-functions-arg-enabled-checkers.c b/clang/test/Analysis/std-c-library-functions-arg-enabled-checkers.c index b388c31..77fa037 100644 --- a/clang/test/Analysis/std-c-library-functions-arg-enabled-checkers.c +++ b/clang/test/Analysis/std-c-library-functions-arg-enabled-checkers.c @@ -28,7 +28,6 @@ // CHECK-NEXT: core.NonNullParamChecker // CHECK-NEXT: core.NonnilStringConstants // CHECK-NEXT: core.NullDereference -// CHECK-NEXT: core.StackAddrEscapeBase // CHECK-NEXT: core.StackAddressEscape // CHECK-NEXT: core.UndefinedBinaryOperatorResult // CHECK-NEXT: core.VLASize |