FFTW FAQ - Section 5
Known bugs
This bug was fixed in FFTW 1.2. There was a bug in
rfftwnd
causing an incorrect amount of memory to be allocated. The bug showed
up in Linux with libc-5.3.12 (and nowhere else that we know of).
These bugs were corrected in FFTW 1.2.1. The MPI transforms (really,
just the transpose routines) in FFTW 1.2 had bugs that could cause
errors in some situations.
This bug was fixed in FFTW 1.3. (Older versions of FFTW did
work in single precision, but the test programs didn't--the error
tolerances in the tests were set for double precision.)
This bug was fixed in FFTW 1.3. FFTW 1.2.1 produced the right answer,
but the test program was wrong. For large n, n*n in the naive
transform that we used for comparison overflows 32 bit integer
precision, breaking the test.
We had problems with glibc-2.0.5. The code should work with
glibc-2.0.7.
This bug was fixed in FFTW 2.0.1. (There was a 32-bit integer
overflow due to a poorly-parenthesized expression.)
There was a bug in the complex transforms that could cause incorrect
results under rare circumstances for lengths with intermediate-size
prime factors (17-97). This bug was fixed in FFTW 2.1.1.
Back: Internals of FFTW.
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Matteo Frigo and Steven G. Johnson / fftw@theory.lcs.mit.edu
- 30 March 1999
Extracted from FFTW Frequently Asked Questions with Answers,
Copyright © 1999 Massachusetts Institute of Technology.