[solved]empty cuda file can affect speed in program?

Hello, i’m CUDA newbie : ))

i have two projects which are same project setting and all sources.
just difference, one project has *.cu, the other project hasn’t .cu file.
(
.cu file is a empty cuda file)

when I run two projects, there are differences in execution time.
(one project with cuda file is faster than the other project, always!)

i don’t understand this situation. ;)

please help me!!!

Sorry, it’s my mistake ; ).

i forgot that i used CUDA’s math functions :(…

Thanks for reading my question !!!