[newlib-cygwin/main] For GCC, newlib combined tree, newlib build-tree testing, use standard search paths

[newlib-cygwin/main] For GCC, newlib combined tree, newlib build-tree testing, use standard search paths

[Thomas Schwinge]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=4c7d0dfec5793cbf5cf3930b91f930479126d8ce

commit 4c7d0dfec5793cbf5cf3930b91f930479126d8ce
Author: Thomas Schwinge <thomas@codesourcery.com>
Date:   Fri Apr 14 21:26:32 2023 +0200

    For GCC, newlib combined tree, newlib build-tree testing, use standard search paths
    
    For example, for GCC/GCN target (AMD GPUs), target libraries are built
    individually per supported hardware ISA ('-march=[...]').  Testing such a
    toolchain via, for example:
    
        $ make RUNTESTFLAGS='--target_board=[...]/-march=gfx90a' check[...]
    
    ... does work fine for all 'check-gcc-[...]' as well as GCC-provided target
    libraries, 'check-target-[...]'.  Just for 'check-target-newlib', for the
    example above, not the '-march=gfx90a' newlib libraries are linked in, but
    instead always the default ones, which results in link FAILure.  This is cured
    simply by skipping use of 'newlib/testsuite/lib/flags.exp', so that the
    standard search paths as determined by GCC, DejaGnu are used for newlib, too.

Diff:
---
 newlib/testsuite/lib/flags.exp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/newlib/testsuite/lib/flags.exp b/newlib/testsuite/lib/flags.exp
index e1e9acb18..697291e7a 100644
--- a/newlib/testsuite/lib/flags.exp
+++ b/newlib/testsuite/lib/flags.exp
@@ -4,6 +4,13 @@
 # is freely granted, provided that this notice is preserved.
 #
 
+if [info exists env(XGCC_FLAGS_FOR_TARGET)] {
+    verbose "GCC, newlib combined tree, build-tree testing; using standard search paths"
+    # ... instead of the search paths built here, based on 'objdir' as set in
+    # newlib's 'site.exp', which always points to the default multilib.
+    return
+}
+
 # flags.exp: overrides the dejagnu versions of libgloss_link_flags,
 # newlib_link_flags, and newlib_include_flags.