On Jan-12, Nicholas Clark wrote:
> IIRC Leo added an option to Configure.pl to turn on optimising.
>
> Prior to this, on IRC Dan said to me that we need to avoid the hack that perl5
> found itself in, when it had to retro-fit the ability to change the compiler
> flags per file.
>
> Currently I don't think we have this ability. I was wondering if we could do
> it by specifying the optimiser flags in the form of
>
> /.../=xxx
> !...!=xxx
>
> yyy
>
> where the first two give a regular expression for the object file(s) we wish
> flags xxx to apply to. The alternative of !! for m!! should be allowed so
> that paths can be specified in the object files as needed, without shell
> escaping. All paths should be in Unix forward slash format, to reduce
> potential confusion. If there are no flags, then yyy applies to all other
> files.
Would it be better to do it the other way around? We could put a
marker at the end of each source file (mixed in with the emacs/vi flag
section?) that specifies a set of compiler flags (or nothing at all if
the default is ok.)
If so, then I'd probably also use named sets ("big-jumptable-flags")
or maybe even named modifiers ("default but violates-aliasing and
trips-gcc2.95-O3-bug"). This would allow better descriptions of why
the flags were being modified, and allow each compiler to deal with
the situation differently (for "violates-aliasing", gcc would add
-fno-strict-aliasing, lcc wouldn't do anything.)
I'm assuming the Configure system extracts the information from the
source files and generates a makefile entry per source file with the
appropriate compiler flags.
