prevent to library from being serialized at precompile time

[KristofferC]

The interpolated variable libfftw3 will evaluate at precompile time to the path to the local directory of the fftw library. This means that if you e.g. build a sysimage using FFTW and move it somewhere else that sysimage will not work properly. Instead, use :libfftw3 which evaluates to the variable libfftw3 which is set during runtime. This is likely what was originally intended.

cc @staticfloat @giordano @andreasnoack

[codecov]

Codecov Report

Merging #197 (8320c0a) into master (53fe689) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #197   +/-   ##
=======================================
  Coverage   62.79%   62.79%           
=======================================
  Files           5        5           
  Lines         422      422           
=======================================
  Hits          265      265           
  Misses        157      157           

Impacted Files	Coverage Δ
src/fft.jl	63.44% <ø> (ø)

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[andreasnoack]

It would be great with a new release that includes this fix.

[ararslan]

FYI master is now 1.6 only, so if we wanted a patch with this we'd need to do a backport, right?

[andreasnoack]

1.6 is all I need