[PATCH 0/3] GNAT test suite fixes for build sysroot

[Maciej W. Rozycki]

Hi,

 In the course of setting up GCC regression testing for the RISC-V target 
I have discovered that the GNAT test suite does not correctly respond to 
the test environment settings passed from the test harness in my setup and 
consequently no test case works correctly.

 In my particular setup `--with-build-sysroot=' has been used to configure 
GCC and also additional linker flags are defined in the target board so 
that adjusted paths are used for the dynamic loader and shared libraries 
to be found in the build sysroot at the test suite run time.  That plays 
well with most of the test suites included with GCC, but not the GNAT one.

 I have tracked down the cause to three issues spread across `gnatmake', 
the GNAT test driver and the DejaGNU target driver.  These issues are 
independent from each other, however all have to be addressed for the test 
suite to run, so I have decided to group them into a series despite that 
each of them can be applied separately, and the DejaGNU one goes to a 
separate project even.

 With them all in place I get these results with the `riscv64-linux-gnu'
target:

                === gnat Summary ===

# of expected passes            2926
# of unexpected failures        5
# of expected failures          23
# of unsupported tests          26

which I think are pretty good, especially compared to the original results 
without these changes:

                === gnat Summary ===

# of expected passes            1580
# of unexpected failures        133
# of unexpected successes       23
# of unresolved testcases       875
# of unsupported tests          26

 See individual change descriptions for details.

  Maciej