Re: TONYC TPF Grant 7 report 11

On Tue, Jun 14, 2016 at 06:30:04PM +1000, Tony Cook wrote:
>  1.85           win32 XS-APItest t/win32.t local failures
> =====
>  4.36
> 
> 2016/06/01      Wednesday
>  1.75           win32 XS-APItest t/win32.t local failures
>  3.98           win32 XS-APItest t/win32.t local failures
> =====
>  5.73

Actually I was planning on writing this one up - mostly with a copy
and paste from the commit message:

    Encountered while testing locally on Windows 7 x64.
    
    cmd.exe stores the current directory for each drive as entries in the
    environment, like:
    
      C:\Users\tony>set "" | findstr "^="
      =::=::\
      =C:=C:\Users\tony
      =D:=D:\ASM1061
    
    When a Win32 build of perl built with USE_IMP_SYS starts up it saves
    the current directories of each drive in a per-thread structure so
    that each pseudo-forked process can have it's own set of drive current
    directories.
    
    If you run an external command, some versions of cmd.exe will add
    an entry to the environment storing the result of that command, for
    example:
    
      C:\Users\tony>set "" | find "ExitCode"
    
      C:\Users\tony>git status
      fatal: Not a git repository (or any of the parent directories): .git
    
      C:\Users\tony>set "" | find "ExitCode"
      =ExitCode=00000080
    
    which is similar to the current directory entries.
    
    The sloppy parsing by VDir::FromEnv[WA]() would treat that as a
    current directory entry for the E: drive, copying the "tCode=...."
    into the current directory.  Normally these values include a leading
    drive letter and \, like "E:\", but this case leaves us without that.
    
    Later, when harness spawns the child process it builds a new environment
    block, including the drive current directories, which is done by
    VDir::BuildEnvironmentSpace().  This, rather than using the index of
    the drive to build the "=C:=..." entries above, uses the first
    letter of the stored entry, so the environment block would have
    something like:
    
      =t:=tCode=00000080
    
    which the child perl would treat as the current directory for the T:
    drive.

The fix was to make the parsing in VDir::FromEnv[WA] less sloppy, as
in d2bccf1b4e37b11ff1a8260cedb2164e0f382dcb.

• TONYC TPF Grant 7 report 11 by Tony Cook
• Re: TONYC TPF Grant 7 report 11 by Tony Cook
• Re: TONYC TPF Grant 7 report 11 by Sawyer X