Thread: single vs double quotes

Originally Posted by laserlight

C99 section 6.3.2.3 states that "any pointer type may be converted to an integer type. Except as previously specified, the result is implementation-defined. If the result cannot be represented in the integer type, the behavior is undefined. The result need not be in the range of values of any integer type."

Now, "bar" is of type const char[4], so we have the usual conversion to const char*, thus it seems that initialising an int with "bar" is not necessarily an error in C, though it is almost certainly a mistake.

It's an error. The C standard is organized even worse than the C++ standard, but 6.5.4p3 says, "Conversions that involve pointers, other than where permitted by the constraints of 6.5.16.1, shall be specified by means of an explicit cast."
And said section permits, paraphrased:
1) Conversion between arithmetic types.
2) Conversion between compatible structures and unions.
3) Conversion between pointers to compatible types, where cv qualification is not lost.
4) Conversion between void* and other pointer types, where cv qualification is not lost.
5) Conversion from a null pointer constant to a pointer.
6) Conversion from a pointer to _Bool.

Originally Posted by Raigne

Microsoft Visual C++ 2008 does not raise an error with

Code:

int t = 'abcd';
//Actually the value is 1633837924

and also does not raise error with

Code:

int t = "abcd";
//the value is 4211020

Hmm ... what mode (C or C++) and warning level? There should be at least a warning. (There's an awful lot of really, really bad legacy C code out there, which is why most compilers accept the code. But they should still warn.)