// RUN: %clang_cc1 -verify=gnu -std=gnu++11 %s | |
// RUN: %clang_cc1 -verify=expected,cxx11 -Wvla -std=gnu++11 %s | |
// RUN: %clang_cc1 -verify=expected,cxx11 -std=c++11 %s | |
// RUN: %clang_cc1 -verify=expected,cxx98 -std=c++98 %s | |
// RUN: %clang_cc1 -verify=expected,off -std=c++11 -Wno-vla-extension-static-assert %s | |
// gnu-no-diagnostics | |
// Demonstrate that we do not diagnose use of VLAs by default in GNU mode, but | |
// we do diagnose them in C++ mode. Also note that we suggest use of | |
// static_assert, but only in C++11 and later and only if the warning group is | |
// not disabled. | |
// C++98 mode does not emit the same notes as C++11 mode because in C++98, | |
// we're looking for an integer constant expression, whereas in C++11 and later, | |
// we're looking for a constant expression that is of integer type (these are | |
// different operations; ICE looks at the syntactic form of the expression, but | |
// C++11 constant expressions require calculating the expression value). | |
void func(int n) { // cxx11-note {{declared here}} off-note {{declared here}} | |
int vla[n]; // expected-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} \ | |
off-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
} | |
void old_style_static_assert(int n) { // cxx11-note 5 {{declared here}} off-note 2 {{declared here}} | |
int array1[n != 12 ? 1 : -1]; // cxx11-warning {{variable length arrays in C++ are a Clang extension; did you mean to use 'static_assert'?}} \ | |
cxx98-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
int array2[n != 12 ? -1 : 1]; // cxx11-warning {{variable length arrays in C++ are a Clang extension; did you mean to use 'static_assert'?}} \ | |
cxx98-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
int array3[n != 12 ? 1 : n]; // expected-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} \ | |
off-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
int array4[(n ? 1 : -1)]; // cxx11-warning {{variable length arrays in C++ are a Clang extension; did you mean to use 'static_assert'?}} \ | |
cxx98-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
int array5[n ? 1 : 0]; // expected-warning {{variable length arrays in C++ are a Clang extension}} \ | |
cxx11-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} \ | |
off-note {{function parameter 'n' with unknown value cannot be used in a constant expression}} | |
} |