re PR d/87824 (x86_64-linux multilib issues)

	PR d/87824
	* lib/gdc.exp (gdc_include_flags): Find C++ headers by calling
	libstdc++v3/scripts/testsuite_flags.  Filter out unsupported
	-nostdinc++ flag.

From-SVN: r269625

gcc/testsuite/ChangeLog

+2019-03-12  Uroš Bizjak  <ubizjak@gmail.com>
+
+	PR d/87824
+	* lib/gdc.exp (gdc_include_flags): Find C++ headers by calling
+	libstdc++v3/scripts/testsuite_flags.  Filter out unsupported
+	-nostdinc++ flag.
+
 2019-03-12  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/87673
@@ -9,8 +16,7 @@
 
 2019-03-12  Martin Liska  <mliska@suse.cz>
 
-	* gfortran.dg/abstract_type_3.f03: Amend test-case scan
-	patterns.
+	* gfortran.dg/abstract_type_3.f03: Amend test-case scan patterns.
 	* gfortran.dg/binding_label_tests_4.f03: Likewise.
 	* gfortran.dg/c_f_pointer_tests_6.f90: Likewise.
 	* gfortran.dg/c_funloc_tests_6.f90: Likewise.

gcc/testsuite/lib/gdc.exp

@@ -88,14 +88,13 @@ proc gdc_include_flags { paths } {
     append flags "-I${srcdir}/../../libphobos/libdruntime "
     append flags "-I${srcdir}/../../libphobos/src "
 
-    # For the tests that mix C++ and D, we should try and handle this better.
-    if { $gccpath != "" } {
-	if [file exists "${gccpath}/libstdc++-v3/include"] {
-	    append flags "-I${gccpath}/libstdc++-v3/include "
-	    append flags "-I${gccpath}/libstdc++-v3/include/$target "
-	}
+    # For the tests that mix C++ and D, need to know where headers are located.
+    set odir [lookfor_file ${gccpath} libstdc++-v3]
+    if { ${odir} != "" } {
+	set cxxflags [exec sh ${odir}/scripts/testsuite_flags --build-includes]
+	set idx [lsearch $cxxflags "-nostdinc++"]
+	append flags [lreplace $cxxflags $idx $idx]
     }
-    append flags "-I${srcdir}/../../libstdc++-v3/libsupc++"
 }
 
 #