Re: [PATCH] gcc: Fix sysroot relative paths for MinGW

[Jeff Law <law at redhat dot com>]

On 10/08/2016 04:26 AM, Tadek Kijkowski wrote:
> Prevent paths relative to sysroot directory from being transformed to
> Windows form with MSYS prefix.
>
> Second attempt:
> Moved most changes to x-mingw32. Only thing added to Makefile.in are new
> variables to ease overriding in included file.
> Disabled overriding standard lib and include paths (with /mingw/lib and
> /mingw/include) in mingw32.h when TARGET_SYSTEM_ROOT is defined.
Host fragments (x-foo files) are strongly discouraged.  The developer 
docs suggest they should only be used for makefile dependencies. 
Practice is somewhat looser than that.  This stuff is so ugly that I'd 
really prefer it be buried, so I think it deserves an exception to the 
guidelines.  But if you need further stuff in this space, let's try to 
avoid additional host fragments.

There's several other directories that are not over-ridden, presumably 
because they're not relative to sysroot?


> Target s-selftest in gcc fails on MinGW:
> /home/tadek/gcc/gcc-build-mingw32-sysroot/./gcc/xgcc
> -B/home/tadek/gcc/gcc-build-mingw32-sysroot/./gcc/ -xc -S -c /dev/null
> -fself-test
> cc1.exe: fatal error: input file 'nul.s' is the same as output file
> It's enough to specify any output file, like '-o self-test-result.s' to
> fix the issue. Specifying '-o /dev/null' works as well, but I'm not sure
> if it's safe on all systems. It's a topic for separate patch.
I think you're supposed to use HOST_BIT_BUCKET instead of /dev/null. 
That can be a follow-up patch.




> Manual at "https://gcc.gnu.org/install/configure.html"; does mention that
> path specified with|--with-native-system-header-dir is located within
> sysroot, but it fails to mention that the same applies to
> ||--with-local-prefix.


 Changelog: 2016-10-08 Tadek Kijkowski> <tkijkowski@gmail.com>

* gcc/Makefile.in, gcc/config/i386/x-mingw32:
> |Fix sysroot relative paths for MinGW
>     * gcc/config/i386/mingw32.h: Disable overriding default library and
> include paths when sysroot is defined
I'm going to go ahead and installon the trunk.  Thanks for updating the 
documentation on what those little makefile fragments do.  It'll be 
helpful if anyone ever needs to change them in the future.


Thanks,
Jeff