Click here to Skip to main content
16,005,120 members
Home / Discussions / C / C++ / MFC
   

C / C++ / MFC

 
GeneralRe: swap Red and Blue in GDI+ Pin
ilidan25-May-06 20:14
ilidan25-May-06 20:14 
Questionpointer [modified] Pin
jith - iii25-May-06 18:45
jith - iii25-May-06 18:45 
AnswerRe: pointer Pin
PJ Arends25-May-06 18:59
professionalPJ Arends25-May-06 18:59 
AnswerRe: pointer Pin
S. Senthil Kumar25-May-06 19:04
S. Senthil Kumar25-May-06 19:04 
GeneralRe: pointer Pin
jith - iii25-May-06 19:22
jith - iii25-May-06 19:22 
GeneralRe: pointer Pin
S. Senthil Kumar25-May-06 19:52
S. Senthil Kumar25-May-06 19:52 
GeneralRe: pointer [modified] Pin
jith - iii25-May-06 21:09
jith - iii25-May-06 21:09 
GeneralRe: pointer Pin
S. Senthil Kumar25-May-06 22:59
S. Senthil Kumar25-May-06 22:59 
jithAtran - ii wrote:
Does the compiler holds anything like a stack to store the datatype?

No, and there is no reason to. At compile time, the compiler knows that p is a pointer to int and q is a pointer to float, so when you do *p or *q, it knows how many bytes to read to get the value, so it generates code to do that. So if you write to a pointer with code like *p = 2 it generates code to write to the first four (or two, in your example) bytes of the address pointed to by p.

So yeah, at runtime, there is no information available about the pointer. The compiler cannot prevent code like this from crashing
char a = 'a';
char *pChar = &a;
void *pVoid = pChar;
int *pInt = (int *)pVoid;
*pInt = 12345;
At runtime, the last line will cause problems, as 4 bytes will be written where only one byte has been allocated. The compiler cannot catch such problems, because it does not store the information anywhere.


Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro
GeneralRe: pointer [modified] Pin
jith - iii25-May-06 23:31
jith - iii25-May-06 23:31 
GeneralRe: pointer [modified] Pin
S. Senthil Kumar26-May-06 14:27
S. Senthil Kumar26-May-06 14:27 
GeneralRe: pointer [modified] Pin
jith - iii26-May-06 19:02
jith - iii26-May-06 19:02 
GeneralRe: pointer [modified] Pin
S. Senthil Kumar26-May-06 20:42
S. Senthil Kumar26-May-06 20:42 
GeneralRe: pointer [modified] Pin
jith - iii26-May-06 22:30
jith - iii26-May-06 22:30 
GeneralRe: pointer [modified] Pin
Stephen Hewitt26-May-06 18:05
Stephen Hewitt26-May-06 18:05 
GeneralRe: pointer [modified] Pin
S. Senthil Kumar26-May-06 20:35
S. Senthil Kumar26-May-06 20:35 
AnswerRe: pointer [modified] Pin
Member 303984325-May-06 19:29
Member 303984325-May-06 19:29 
AnswerRe: pointer [modified] Pin
Saday Sarkar25-May-06 19:51
Saday Sarkar25-May-06 19:51 
GeneralRe: pointer [modified] Pin
jith - iii25-May-06 21:11
jith - iii25-May-06 21:11 
GeneralRe: pointer [modified] Pin
Stephen Hewitt26-May-06 18:25
Stephen Hewitt26-May-06 18:25 
GeneralRe: pointer [modified] Pin
jith - iii26-May-06 19:06
jith - iii26-May-06 19:06 
QuestionLinux's gettimeofday() equivalent for windows Pin
useme12325-May-06 18:41
useme12325-May-06 18:41 
AnswerRe: Linux's gettimeofday() equivalent for windows Pin
Ganesh_T25-May-06 18:51
Ganesh_T25-May-06 18:51 
GeneralRe: Linux's gettimeofday() equivalent for windows Pin
ThatsAlok25-May-06 22:18
ThatsAlok25-May-06 22:18 
AnswerRe: Linux's gettimeofday() equivalent for windows Pin
Nibu babu thomas25-May-06 18:53
Nibu babu thomas25-May-06 18:53 
AnswerRe: Linux's gettimeofday() equivalent for windows Pin
Ryan Binns25-May-06 18:57
Ryan Binns25-May-06 18:57 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.