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jacob: lcc64 compiler -1 vs DWORD_PTR compare problem
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johnco...@gmail.com
May 17, 2013, 7:33:51 AM5/17/13
to
compiled with lcc64
int main()
{
int r = -1;
DWORD_PTR zero = 0;
if (r > zero) printf("r > 0\n");
}
it will print 'r>0'
i'm not sure is this compiler bug or not, but it makes a lot of problems with win32--->win64 code migration.
-1 is used in SOCKET_ERROR and INVALID_HANDLE_VALUE
workaround:
if (r>(int)zero) will work ok.
int main()
{
int r = -1;
DWORD_PTR zero = 0;
if (r > zero) printf("r > 0\n");
}
it will print 'r>0'
i'm not sure is this compiler bug or not, but it makes a lot of problems with win32--->win64 code migration.
-1 is used in SOCKET_ERROR and INVALID_HANDLE_VALUE
workaround:
if (r>(int)zero) will work ok.
jacob navia
May 17, 2013, 10:44:51 AM5/17/13
to
Le 17/05/13 13:33, johnco...@gmail.com a �crit :
DWORD is an <unsigned> int.
R will be converted to unsigned, i.e. to 0xffffffff, that is 4294967295.
Since 4294967295 is bigger than zero, the result is what you get.
Please remember
Comparisons between signed/unsigned types are risky.
R will be converted to unsigned, i.e. to 0xffffffff, that is 4294967295.
Since 4294967295 is bigger than zero, the result is what you get.
Please remember
Comparisons between signed/unsigned types are risky.
Jeb
Jun 9, 2013, 5:36:55 AM6/9/13
to
jacob navia wrote:
[idiocy]
You are an idiot. :P
[idiocy]
You are an idiot. :P
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