Casting, c programming

Question

I got confused in interpreting this line:

a = (char*) b;

while a and b are both declared to be of type char*.

Can anyone explain it to me please?

If they are both declared char * then above code is equivalent to a =b; — Riz, Mar 06 '14 at 01:39
It would just ignore the cast. Maybe `b` used to be something else in previous versions of the code, and they never removed the now unnecessary cast? — Mike Christensen, Mar 06 '14 at 01:40

score 2 · Answer 1 · edited May 04 '15 at 16:00

2

If they are of the same type, there is no need to use casting in the expression and it is the same as

a = b;

Edit: example casting with pointers

If you are using a C++ compiler, you need casting when calling malloc function otherwise you get an error message. This function returns a void* pointer and you need to explicitly cast it to its destination type as implicit conversion from void* has not been inherited from C.

edited May 04 '15 at 16:00

Quentin

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answered May 04 '15 at 14:48

bpinhosilva

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No, no, no, no, no, [noooo](http://stackoverflow.com/a/605858/3233393). The compiler does not need your help with the result of `malloc`. – Quentin May 04 '15 at 14:53
Thanks for the point, but some compiler versions still send a warning when the cast is not present. – bpinhosilva May 04 '15 at 14:56
If they *are* C compilers (not C++), then they are badly broken. No spreading of misinformation in favor of a braindead compiler without mention, please... -1 gone ;) – Quentin May 04 '15 at 14:57

Casting, c programming

1 Answers1