https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84868
--- Comment #16 from Paul Thomas <pault at gcc dot gnu.org> --- Created attachment 58641 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58641&action=edit Fix for this PR The only way that I have found to fix this is to simplify the len_trim expression. In doing so, another parameter has to be created for which I have taken a leaf out of the unique_name mechanism. Unfortunately, two such parameters are created (parsing specification expression and then resolution), the first one of which is unused. I don't see any easy way to eliminate it. I came across another bug in testing variants, which is also fixed. Regtests OK. I'll think further about doubling up on the parameter before submitting. Paul