On Thu, 26 Dec 2019, Alexandre Oliva wrote:
> On Dec 25, 2019, Alexandre Oliva <ol...@adacore.com> wrote:
>
> > 3. do not take the executable name into account when it shares the
> > basename with an input file; combine executable basename with input name
> > otherwise. this makes gcc -o foo[.exe] -g -gsplit-dwarf foo.c output
> > foo.dwo rather than foo-foo.dwo, which is nice, but then dwo files
> > compiled for use with foo won't all match foo-*.dwo; it seems more
> > desirable that they all do
>
> > 4. same as above, but only when there is only one input file, so that
> > after adding bar.c to the command above, you'd get foo-foo.dwo and
> > foo-bar.dwo
>
> > Me, I'm leaning towards 5.
>
> And yet I ended up implementing 4 after some more thinking, because the
> point was to reduce gratuitous and unnecessary changes.
>
>
> Here's my first cut at documenting all of the various complex
> interactions between -o, -dumpbase, -dumpbase-ext, -dumpdir, and
> save-temps=*
>
> Is this too cryptic, to the point of requiring lots of examples to make
> it understandable, or is this usable enough?
It's understandable and indeed also very helpful. So I agree to go
forward with this (variant 4).
Did I miss the actual (non-documentation) patch?
Thanks,
Richard.
>
> @@ -1561,6 +1563,89 @@ assembler file in @file{@var{source}.s}, a precompiled
> header file in
> @file{@var{source}.@var{suffix}.gch}, and all preprocessed C source on
> standard output.
>
> +
> +@item -dumpbase @var{dumpbase}
> +@opindex dumpbase
> +This option sets the base name for auxiliary and dump output files. It
> +does not affect the name of the main output file, implied or specified
> +with @option{-o}. It may affect intermediate outputs, however:
> +
> +@smallexample
> +gcc -save-temps -S foo.c&
> +@end smallexample
> +
> +saves the (no longer) temporary preprocessed file in @file{foo.i}, and
> +then compiles to the (implied) output file @file{foo.s}, whereas:
> +
> +@smallexample
> +gcc -save-temps -dumpbase save-foo -c foo.c&
> +@end smallexample
> +
> +preprocesses to in @file{save-foo.i}, compiles to @file{save-foo.s} (now
> +an intermediate, thus auxiliary output), and then assembles to the
> +(implied) output file @file{foo.o}.
> +
> +If absent, dump and aux files their names from the input file, or from
> +the (non-linker) output file, if one is explicitly specified: dump
> +output files (e.g. those requested by -fdump-* options) with the input
> +name suffix, and aux output files (those requested by other non-dump
> +options, e.g. @code{-save-temps}, @code{-gsplit-dwarf},
> +@code{-fcallgraph-info}) without it.
> +
> +Similar suffix differentiation of dump and aux outputs can be attained
> +for explicitly-given @option{-dumpbase basename.suf} by also specifying
> +@option{-dumpbase-ext .suf}.
> +
> +If @var{dumpbase} is explicitly specified with any directory component,
> +@option{-dumpdir} and other @var{dumppfx}-setting @option{-save-temps=*}
> +options are ignored, and instead of appending to it, @var{dumpbase}
> +fully overrides it.
> +
> +When @option{-dumpbase} is specified in a command that compiles multiple
> +inputs, or that compiles and then links, it may be combined with
> +@var{dumppfx}, as specified under @option{-dumpdir}, and each input file
> +is then compiled using the combined @var{dumppfx}, and default values
> +for @var{dumpbase} and @var{auxdropsuf} computed for each input file.
> +
> +
> +@item -dumpbase-ext @var{auxdropsuf}
> +@opindex dumpbase-ext
> +When forming the name of an auxiliary (but not a dump) output file, drop
> +trailing @var{auxdropsuf} from @var{dumpbase} before appending any
> +suffixes. If not specified, this option defaults to the suffix of the
> +input file, including the period.
> +
> +
> +@item -dumpdir @var{dumppfx}
> +@opindex dumpdir
> +When forming the name of an auxiliary or dump output file, use
> +@var{dumppfx} as a prefix. If it is to be used as a directory name, it
> +must end with a directory separator.
> +
> +It defaults to the location of the output file; options
> +@option{-save-temps=cwd} and @option{-save-temps=obj} override this
> +default, just like an explicit @option{-dumpdir} option. In case
> +multiple such options are given, the last one prevails.
> +
> +When compiling from multiple input files, if @option{-dumpbase} is
> +specified, @var{dumpbase}, minus a @var{auxdropsuf} suffix, and a dash
> +are appended to (or override, if containing any directory components) an
> +explicit or defaulted @var{dumppfx}, so that each of the multiple
> +compilations gets differently-named aux and dump outputs.
> +
> +When compiling and then linking from multiple input files, a defaulted
> +or explicitly specified @var{dumppfx} also undergoes the @var{dumpbase}-
> +transformation above. If neither @option{-dumpdir} nor
> +@option{-dumpbase} are given, the linker output base name, minus the
> +executable suffix, plus a dash is appended to the default @var{dumppfx}
> +instead.
> +
> +When compiling and then linking from a single input file, the linker
> +output base name will only be appended to the default @var{dumppfx} as
> +above if it does not share the base name with the single input file
> +name.
> +
> +
> @item -v
> @opindex v
> Print (on standard error output) the commands executed to run the stages
>
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)
