Have you tested the results with a calculator or language that works with double precision?
Here all your results of your demo are wrong
Multiply 36337.58583466*4792.94923023755
Your DLL: 174164208
Windows Calculator: 174164204.054924547826823483
PureBasic: 174164204.05492455
Divide 36337.58583466/4792.94923023755
Your DLL: 7.5814666748046875
Windows Calculator 7.5814668775156257065644242414405
PureBasic: 7.5814668775156253
This is the same I ran into several month ago when I made a dll with double precision ... the dll works fine until it gets into the Blitz3D environment. Blitz3D blocks the CPU working with doubles! You get a result, but its wrong after the 7th digit.
I worked around it that way: I made a standalone exe instead of a dll - sending and getting variables via TCP. Not very quick but in the case I needed it for it was quick enough to do the job. Another way was communication between the 2 Programs though a file.
Since a standalone exe with double precision works perfect and 3 different dlls (my PureBasic, my PowerBasic and your VisualC) fail, it can only be Blitz3D making trouble.
Btw.: My dlls worked errorfree with other languages! Have not tried this dll though... but I presume it will, too.
http://www.blitzbasic.com/Community/posts.php?topic=58828#654531
.
Here all your results of your demo are wrong
Multiply 36337.58583466*4792.94923023755
Your DLL: 174164208
Windows Calculator: 174164204.054924547826823483
PureBasic: 174164204.05492455
Divide 36337.58583466/4792.94923023755
Your DLL: 7.5814666748046875
Windows Calculator 7.5814668775156257065644242414405
PureBasic: 7.5814668775156253
This is the same I ran into several month ago when I made a dll with double precision ... the dll works fine until it gets into the Blitz3D environment. Blitz3D blocks the CPU working with doubles! You get a result, but its wrong after the 7th digit.
I worked around it that way: I made a standalone exe instead of a dll - sending and getting variables via TCP. Not very quick but in the case I needed it for it was quick enough to do the job. Another way was communication between the 2 Programs though a file.
Since a standalone exe with double precision works perfect and 3 different dlls (my PureBasic, my PowerBasic and your VisualC) fail, it can only be Blitz3D making trouble.
Btw.: My dlls worked errorfree with other languages! Have not tried this dll though... but I presume it will, too.
http://www.blitzbasic.com/Community/posts.php?topic=58828#654531
.