However, it's just occurred to me that the executable actually doesn't do anything.
Could it be that success is achieved only because the problem I'm trying to expose is being optimised away ?

So, I made the test executable actually do something, and uploaded a new version (0.14) of Math::LongDouble.
Unfortunately, I still get the same failure reports from Bingos' NetBSD smoker(s), and the test executable works fine.

I guess the next thing is to try compiling the test executable using the same cflags ($Config{ccflags}) as are used during the module build.
So, I'll try that.
Should I also include $Config{ldflags} in the build of the test executable ?
Any other ideas ? (Any other flags to include ?)

Cheers,
Rob