Explain gfortran-dg-runtest usage in libgomp Fortran testing.

	libgomp/
	* testsuite/libgomp.fortran/fortran.exp: Explain
	gfortran-dg-runtest usage.

From-SVN: r212266

libgomp/ChangeLog

+2014-07-03  Thomas Schwinge  <thomas@codesourcery.com>
+
+	* testsuite/libgomp.fortran/fortran.exp: Explain
+	gfortran-dg-runtest usage.
+
 2014-06-25  Jakub Jelinek  <jakub@redhat.com>
 
 	* testsuite/libgomp.fortran/simd5.f90: New test.

libgomp/testsuite/libgomp.fortran/fortran.exp

@@ -59,7 +59,9 @@ if { $lang_test_file_found } {
     append ld_library_path [gcc-set-multilib-library-path $GCC_UNDER_TEST]
     set_ld_library_path_env_vars
 
-    # Main loop.
+    # For Fortran we're doing torture testing, as Fortran has far more tests
+    # with arrays etc. that testing just -O0 or -O2 is insufficient, that is
+    # typically not the case for C/C++.
     gfortran-dg-runtest $tests ""
 }