It's probably the calling convention. Change your C to:
double __stdcall adnValues(double x, double y)
You can use WINAPI instead of __stdcall (that's 2 underscores) if you #include <windows.h>.

In reply to Re: why Crashing windows API using perl?? by cdarke
in thread why Crashing windows API using perl?? by madtoperl

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