diff options
| -rw-r--r-- | libobjc/objc/objc.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/libobjc/objc/objc.h b/libobjc/objc/objc.h index 79b2519e576..699542c493b 100644 --- a/libobjc/objc/objc.h +++ b/libobjc/objc/objc.h @@ -73,7 +73,14 @@ typedef struct objc_object { /* ** Definition of method type. When retrieving the implementation of a -** method, this is type of the pointer returned +** method, this is type of the pointer returned. The idea of the +** definition of IMP is to represent a 'pointer to a general function +** taking an id, a SEL, followed by other unspecified arguments'. You +** must always cast an IMP to a pointer to a function taking the +** appropriate, specific types for that function, before calling it - +** to make sure the appropriate arguments are passed to it. The code +** generated by the compiler to perform method calls automatically +** does this cast inside method calls. */ typedef id (*IMP)(id, SEL, ...); |