libstdc++: Replace @require@ markup in some I/O tests

We can replace the @require@ markup with { dg-additional-files ... }
directives, so that the required files are explicitly named and are
explicitly copied into place for tests that require it. This will allow
a later change to remove the "Copy all required data files" step in the
proc libstdc++_init in testsuite/lib/libstdc++.exp that is marked TODO.
This commit uses dg-additional-files for a subset of the files that
contain @require@.

Also remove the @diff@ markup where appears to be copy & pasted from
other test files, and so serves no purpose. For example, there is no
output file created by 27_io/basic_ifstream/cons/char/1.cc so there is
nothing for @diff@ to compare. Maybe the purpose was to check that
reading the .tst file with an ifstream doesn't change it, but we've
survived without doing those comparisons for many years so I think we
can remove those cases of @diff@ markup.

libstdc++-v3/ChangeLog:

	* testsuite/27_io/basic_filebuf/close/char/2.cc: Remove
	@require@ and @diff@ markup. Use dg-additional-files. Remove
	unused variable.
	* testsuite/27_io/basic_filebuf/close/char/3.cc: Remove
	@require@ and @diff@ markup. Use dg-additional-files.
	* testsuite/27_io/basic_filebuf/close/char/4.cc: Likewise.
	* testsuite/27_io/basic_filebuf/close/char/5.cc: Likewise.
	* testsuite/27_io/basic_filebuf/in_avail/char/1.cc: Likewise.
	* testsuite/27_io/basic_filebuf/is_open/char/1.cc: Likewise.
	* testsuite/27_io/basic_filebuf/open/char/1.cc: Likewise.
	* testsuite/27_io/basic_filebuf/open/char/2.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sbumpc/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sbumpc/char/1-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sbumpc/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sbumpc/char/2-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekoff/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekoff/char/1-out.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekoff/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekoff/char/2-out.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekpos/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekpos/char/1-out.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekpos/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/seekpos/char/2-out.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetc/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetc/char/1-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetc/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetc/char/2-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetn/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetn/char/1-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetn/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sgetn/char/2-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/snextc/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/snextc/char/1-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/snextc/char/1-out.cc: Likewise.
	* testsuite/27_io/basic_filebuf/snextc/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/snextc/char/2-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sputbackc/char/1-in.cc:
	Likewise.
	* testsuite/27_io/basic_filebuf/sputbackc/char/2-in.cc:
	Likewise.
	* testsuite/27_io/basic_filebuf/sputc/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sputc/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sputc/char/2-io.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sputn/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sputn/char/1-io.cc: Likewise.
	Remove unused variable.
	* testsuite/27_io/basic_filebuf/sputn/char/2-in.cc: Remove
	@require@ and @diff@ markup. Use dg-additional-files.
	* testsuite/27_io/basic_filebuf/sungetc/char/1-in.cc: Likewise.
	* testsuite/27_io/basic_filebuf/sungetc/char/2-in.cc: Likewise.
	* testsuite/27_io/basic_ifstream/cons/char/1.cc: Likewise.
	* testsuite/27_io/basic_ifstream/open/char/1.cc: Likewise.
	* testsuite/27_io/basic_ifstream/rdbuf/char/2832.cc: Likewise.
	* testsuite/27_io/basic_istream/readsome/char/6746-2.cc:
	Likewise.
	* testsuite/27_io/basic_istream/readsome/wchar_t/6746-2.cc:
	Likewise.
	* testsuite/27_io/basic_istream/seekg/char/sstream.cc: Likewise.
	* testsuite/27_io/basic_istream/seekg/wchar_t/sstream.cc:
	Likewise.
	* testsuite/27_io/basic_istream/tellg/char/1.cc: Likewise.
	* testsuite/27_io/basic_istream/tellg/char/sstream.cc: Likewise.
	* testsuite/27_io/basic_istream/tellg/wchar_t/1.cc: Likewise.
	* testsuite/27_io/basic_istream/tellg/wchar_t/sstream.cc:
	Likewise.
	* testsuite/27_io/basic_ofstream/open/char/1.cc: Likewise.
	* testsuite/lib/dg-options.exp (dg-additional-files): Append to
	v3_additional_files instead of replacing.
	* testsuite/lib/libstdc++.exp (v3_target_compile): Reset
	v3_additional_files after copying files.

2 files changed, 2 insertions, 1 deletions

diff --git a/libstdc++-v3/testsuite/lib/dg-options.exp b/libstdc++-v3/testsuite/lib/dg-options.exp
index 0d77fb0..1d31604 100644
--- a/libstdc++-v3/testsuite/lib/dg-options.exp
+++ b/libstdc++-v3/testsuite/lib/dg-options.exp
@@ -405,5 +405,5 @@ set v3_additional_files ""
 # Process a { dg-additional-files "filelist" } directive in the test.
 proc dg-additional-files { line filelist } {
     global v3_additional_files
-    set v3_additional_files $filelist
+    append v3_additional_files " " $filelist
 }
diff --git a/libstdc++-v3/testsuite/lib/libstdc++.exp b/libstdc++-v3/testsuite/lib/libstdc++.exp
index 67a63f5..8efc6f7 100644
--- a/libstdc++-v3/testsuite/lib/libstdc++.exp
+++ b/libstdc++-v3/testsuite/lib/libstdc++.exp
@@ -648,6 +648,7 @@ proc v3_target_compile { source dest type options } {
 	global srcdir
 	v3-copy-file "$srcdir/data/$file" $file
     }
+    set v3_additional_files {}
 
     set comp_output [target_compile $source $dest $type $options]
     if { $type == "executable" && $file_to_delete != "" } {