On 2020/1/6 11:25 PM, Maciej W. Rozycki wrote:
>   Overall if libgomp-test-support.exp is considered appropriate for
> standalone testing, then I think two solutions are possible here:
> 
> 1. An option is added to libgomp's $CC such that the compiler is able to
>     make builds involving the offload compiler where requested, and this
>     then propagates to GCC_UNDER_TEST as it stands.
> 
> 2. The definition of GCC_UNDER_TEST in libgomp-test-support.exp is only
>     made if inexistent, and then you can predefine the variable in site.exp
>     however you find appropriate.

Hi Maciej,
I understand your situation with --with-build-sysroot/--without-sysroot, but the
way you set GCC_UNDER_TEST in libgomp-test-support.exp appears to override too
much of the machinery in libgomp/testsuite/lib/libgomp.exp that sets GCC_UNDER_TEST
using DejaGNU find_gcc, etc.

Can you test if the attached patch works for you? The patch exports the build sysroot
setting from the toplevel to target library subdirs, and adds the --sysroot= option
when doing build-tree testing (I assume that blddir != "" test is sufficient from the
surrounding comments)

I can only verify that it no longer "interferes" with our installed-mode testing.
Also, if this does work, then other library testsuites (e.g. libatomic.exp) might
also need considering updating, I think.

Thanks,
Chung-Lin

2020-01-14  Chung-Lin Tang  <cltang@codesourcery.com>

	* Makefile.tpl	(NORMAL_TARGET_EXPORTS): Add export of
	SYSROOT_CFLAGS_FOR_TARGET variable.
	* Makefile.in:	Regenerate.

	libgomp/
	* testsuite/lib/libgomp.exp (ALWAYS_CFLAGS): Add
	--sysroot=$SYSROOT_CFLAGS_FOR_TARGET option when doing build-tree testing.
	Fix comment typo.
	* testsuite/libgomp-test-support.exp.in (GCC_UNDER_TEST): Delete definition.