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On Mar 6, 2011, at 4:32 PM, Sylvain Fabre wrote:

> I try to send a 32 bits uint32_t value from LUA to C (ie in fact a 0xRRGGBBAA pattern) and i am facing the following issue : 
> 	• If i do a 0xFF0000FF -> I get the value 0x80000000 with luaL_checkinteger()
> 	• If i do not set the MSB (ie 0x7F0000FF for example) -> I get the correct value  with luaL_checkinteger()
> I guess it has something to do with sign conversion, but i do not know if it is a bug or a normal behavior with luaJIT.
> Any hint or idea ?

Try using signed integers.

> =-0x80000000
> =bit.bor(-2147483648,0xff0000ff)