Re: Any compiler ANSI C++ compliant? None I found
In article <455b6cb8$0$5726$9b4e6d93@newsspool3.arcor-online.net>,
vl106 <vl106@hotmail.com> wrote:
I was fiddling around with a problem when I ran into an issue that struke
me.
The following code causes an access violation. Correct. "123" is an array of
const char (that's what the standard says).
Okay. By why do all compilers accept this code? foo("123") should produce
a type mismatch error.
At least Scott Meyers has the same opinion:
[...] is technically illegal (it's a violation of const correctness). In
practice, I expect
all compilers to accept such code [...]
Not so sure, char s[] = "ABC"; is a non const char array large
enough to hold "ABC" and intialized with the data of "ABC", not a
pointer to the const "ABC". That is it is a COPY of "ABC" not "ABC".
I tested Comeau, Digital, Visual and Watcom. All of them accepted the code.
Most binaries worked - only VC crashed as the compiler put the literal in a
const segment.
I for my part plead for C++ leaving its ancestry behind and become a real
typesafe
language!
void foo (char* p) { // accepts "123" and fails!
*p = 'X';
}
int main () {
char s[] = "ABC";
foo (s);
foo ("123"); // Visual C++ will crash!
// Digital, Watcom C++ won't crash!
return 0;
}
Off hand I would say that your VC++ is non compliant. It is treating
it as if main() began with
int main()
{
char *s = "ABC";
// ...
}
which not the same as your main(). Your main says s is a char[4]
intialized to {'A','B','C','\0'} not a pointer to "ABC"; and as such
foo should work with no faults or exceptions.
Maybe you should plead for compliance of your compiler and not
modification of the standard to match a non compliant compiler.
BTW my CW 9 works with your code s becomes "XBC", as expected.
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