Re: [PATCH] testsuite: use cygpath to convert from Unix to Windows paths

[Christian Biesinger <cbiesinger@google.com>]

On Wed, Mar 11, 2020 at 1:32 PM Simon Marchi via Gdb-patches
<gdb-patches@sourceware.org> wrote:
>
> When on a MinGW host, standard_output_file uses a regular expression to
> convert Unix-style paths of the form "/c/foo" to "c:/foo".  This is
> needed because the paths we pass to GDB (for example, with the "file"
> command) need to be in the Windows form.
>
> However, the regexp only works if your binutils-gdb repo is under a
> `/[a-z]/...` path (the Unix paths mapping to Windows drives).
> Presumably, that works if you clone the repo in Windows, then access it
> through `/c/...`.
>
> In my case, I've cloned the repository directly inside my MinGW shell,
> so in /home/smarchi.  The regexp therefore doesn't work for me.  The
> path doesn't get transformed, and the file command fails when running
> any test:
>
>     (gdb) file /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.arch/i386-bp_permanent/i386-bp_permanent
>     /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.arch/i386-bp_permanent/i386-bp_permanent: No such file or directory.
>
> A safer way to do this conversion would be to use the cygpath utility.
> It can be used to convert any MinGW path into its Windows equivalent.
>
> Note that despite originally coming from Cygwin, the cygpath utility is
> distributed by mingw-w64 and can be used in that environment.
>
> With this, the file command in the test succeeds:
>
>     (gdb) file C:/msys64/home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.arch/i386-bp_permanent/i386-bp_permanent
>     Reading symbols from C:/msys64/home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.arch/i386-bp_permanent/i386-bp_permanent...
>
> gdb/testsuite/ChangeLog:
>
>         * lib/gdb.exp (standard_output_file): Use cygpath to convert
>         from Unix to Windows path.
> ---
>  gdb/testsuite/lib/gdb.exp | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
> index 9614e8dc87cd..ac16e0e85c99 100644
> --- a/gdb/testsuite/lib/gdb.exp
> +++ b/gdb/testsuite/lib/gdb.exp
> @@ -4899,8 +4899,10 @@ proc standard_output_file {basename} {
>      file mkdir $dir
>      # If running on MinGW, replace /c/foo with c:/foo
>      if { [ishost *-*-mingw*] } {
> -        set dir [regsub {^/([a-z])/} $dir {\1:/}]
> +       set dir [exec cygpath --mixed "${dir}"]

This is fine, but out of curiosity, why --mixed instead of --windows?

> +
>      }

Why the empty line above?

> +
>      return [file join $dir $basename]
>  }
>
> --
> 2.25.1
>