Compilation mode very slow with large files

[Giuseppe Scelsi]

Hi,

In Emacs 22.1.1 for Windows, when I open a large text file (15 MB) in
fundamental mode and then switch to compilation mode, emacs hangs for
ever, while the status bar displays "Fontifying <filename>...".  I tried
to set '`global-font-lock-mode' to nil, with no success.

Hitting C-g manages to stop the process, but the buffer is left with no
fontification or hot links, in spite of reading '(Compilation)' in the
status bar.

I tried using 'debug-on-entry' and stepping through the code, but this
causes no apparent change in the buffer in spite of the process
terminating successfully with no error messages.

Is this a bug or an expected behaviour?  Does anyone have a suggestion
on how to work around this?  Or any hint about to further debug the
problem?  I am really interested in getting the active click-on links to
the relevant lines of source code, I wouldn't mind if fontification were
switched off.

Thanks in advance.

Giuseppe