code to test warning level of C++ translation unit

warning_level_test.cpp

// code to test warning level of C++ translation unit;
// works with compilers which support `-Wpedantic` flag

// any warning level: 'extern' variable has an initializer [-Wextern-initializer]
// -Wall: "unused variable 'n' [-Wunused-variable]"
// -Wextra: "missing field 'b' initializer [-Wmissing-field-initializers]"
extern struct { int a, b; } n = {sizeof(void(*)(int))};

// -Wpedantic: "variable length arrays are a C99 feature [-Wvla-extension]"
int evoke_pedantic_warning_vla(int n) { int a[n]; return a[3]; }