Thanks Araq. In the end I guessed it was related to stdin/out because I grepped "fileno" into GCC's header files and it came up in the context of filesystem related constants.
Mhhh ... so I might be getting away with a simple Fibonacci function, but get a crash with more complex stuff! I've read many posts of people having problems importing static libs into PureBASIC under Windows, and that using DLL is always simpler. But in this case I was trying to experiment with static libs. I've seen on PureBASIC forums that often errors similar to the ones I got were related to a missing system DLL (like some specific version of MS Visual Studio redistributables, ecc.) and was solved by importing the required DLLs along with the static libs.... I guess that I'll eventually get a grip on this, with more practice and insight into the nebulous world of all these trans-compiler operations --- I mean: soooo many options just for GCC compiler alone! it's east to get lost in this configuration/compatibility jungle. ;)
