diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000000000000000000000000000000000000..3912109b5cd65a68039d473c11c9f7ac2303e06d
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                       51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
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+  To protect your rights, we need to make restrictions that forbid
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+These restrictions translate to certain responsibilities for you if you
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+
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+
+  We protect your rights with two steps: (1) copyright the software, and
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+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
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+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+		    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
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+Activities other than copying, distribution and modification are not
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+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
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+  1. You may copy and distribute verbatim copies of the Program's
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+copyright notice and disclaimer of warranty; keep intact all the
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+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
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+
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+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
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+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
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+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
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+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
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+
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+The source code for a work means the preferred form of the work for
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+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
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+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
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+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
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+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
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+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+			    NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+		     END OF TERMS AND CONDITIONS
+
+	    How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/ParserGeneration.java b/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/ParserGeneration.java
index 2e3a8e7bc7c0b8520d56344bc060b18852f27bdf..d8a65710b8a59d2f00c74e55072ad024cd100207 100644
--- a/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/ParserGeneration.java
+++ b/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/ParserGeneration.java
@@ -94,6 +94,7 @@ public class ParserGeneration {
         "pass along TruffleRLanguage",
         "convert line endings",
         "handle four and more dots as identifier",
-        "allow greek characters in identifiers"
+        "allow greek characters in identifiers",
+        "allow everything but newlines in %<ident>% operators"
     };
 }
diff --git a/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/R.g b/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/R.g
index 8e11dfacc9b097e2e20a305bb50b232f23b9a981..ee3092702168a8da6dc98dc1eb0717e273874404 100644
--- a/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/R.g
+++ b/com.oracle.truffle.r.parser/src/com/oracle/truffle/r/parser/R.g
@@ -695,7 +695,7 @@ ID
     | '`' BACKTICK_NAME
     ;
 
-OP : '%' OP_NAME+ '%' ;
+OP : '%' (~('%' | '\n' | '\r' | '\f'))+ '%' ;
 
 fragment BACKTICK_NAME
     @init { final StringBuilder buf = new StringBuilder(); }
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/data/RPromise.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/data/RPromise.java
index 8b7ff52fec004d9869457e7e8d49c5780ae5ebc5..db83ac5f85b11e51bf639f764170106a24973749 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/data/RPromise.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/data/RPromise.java
@@ -238,7 +238,6 @@ public class RPromise extends RObject implements RTypedValue {
      * @see #execFrame
      */
     public final MaterializedFrame getFrame() {
-        assert !isEvaluated();
         return execFrame;
     }
 
diff --git a/com.oracle.truffle.r.test.packages/gated b/com.oracle.truffle.r.test.packages/gated
index f2bc110186ab1197be4bc81b8e2f610e4beebb18..1e482ce101b7d29bd9028a0521dde91de6cd4c04 100644
--- a/com.oracle.truffle.r.test.packages/gated
+++ b/com.oracle.truffle.r.test.packages/gated
@@ -1 +1,4 @@
 foreign
+mime
+iterators
+rjson
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
index 2a5c05f9d5f5e7d081d06d50d2491a96819121dc..4231476011c26ece8a58fcf9761ecac6eda2daf6 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/ExpectedTestOutput.test
@@ -160766,6 +160766,22 @@ non-integer value 12345678909876543212L qualified with L; using numeric value
 #'\ ' == ' '
 [1] TRUE
 
+##com.oracle.truffle.r.test.parser.TestParser.testUserOp#
+#`%!@#$^&*()%` <- function(a,b) 1; 10 %!@#$^&*()% 20
+[1] 1
+
+##com.oracle.truffle.r.test.parser.TestParser.testUserOp#
+#`%5%` <- function(a,b) 1; 10 %5% 20
+[1] 1
+
+##com.oracle.truffle.r.test.parser.TestParser.testUserOp#
+#`%foo%` <- function(a,b) 1; 10 %foo% 20
+[1] 1
+
+##com.oracle.truffle.r.test.parser.TestParser.testUserOp#
+#`%Š%` <- function(a,b) 1; 10 %Š% 20
+[1] 1
+
 ##com.oracle.truffle.r.test.rffi.TestUserRNG.testUserRNG#
 #{ dyn.load("tmptest/userrng/liburand.so"); RNGkind("user"); print(RNGkind()); set.seed(4567); runif(10) }
 [1] "user-supplied" "Inversion"
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/parser/TestParser.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/parser/TestParser.java
index 9f9de365a6800be6007de366c8609813ea74a528..f2689a28d2d0de17a9b3d3c295862fb759211fbf 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/parser/TestParser.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/parser/TestParser.java
@@ -150,6 +150,14 @@ public class TestParser extends TestBase {
         assertEval("{ ...... <- 42; cat(......); }");
     }
 
+    @Test
+    public void testUserOp() {
+        assertEval("`%foo%` <- function(a,b) 1; 10 %foo% 20");
+        assertEval("`%5%` <- function(a,b) 1; 10 %5% 20");
+        assertEval("`%Š%` <- function(a,b) 1; 10 %Š% 20");
+        assertEval("`%!@#$^&*()%` <- function(a,b) 1; 10 %!@#$^&*()% 20");
+    }
+
     /**
      * Recursively look for .r source files in the args[0] directory and parse them.
      */
diff --git a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/tck/FastRTckTest.java b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/tck/FastRTckTest.java
index 363accb8c931dbb8a2654bd0d5687037f1fa666b..9f678bd062deab3beefb347f76e9a49da118ee7d 100644
--- a/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/tck/FastRTckTest.java
+++ b/com.oracle.truffle.r.test/src/com/oracle/truffle/r/test/tck/FastRTckTest.java
@@ -29,7 +29,7 @@ import org.junit.Test;
 import com.oracle.truffle.api.source.Source;
 import com.oracle.truffle.api.vm.PolyglotEngine;
 import com.oracle.truffle.api.vm.PolyglotEngine.Builder;
-import com.oracle.truffle.r.runtime.RSource;
+import com.oracle.truffle.r.runtime.RRuntime;
 import com.oracle.truffle.tck.TruffleTCK;
 
 public class FastRTckTest extends TruffleTCK {
@@ -40,7 +40,7 @@ public class FastRTckTest extends TruffleTCK {
     }
 
     // @formatter:off
-    private static final Source INITIALIZATION = RSource.fromTextInternal(
+    private static final String INITIALIZATION_CODE =
         "fourtyTwo <- function() {\n" +
         "  42L\n" +
         "}\n" +
@@ -148,11 +148,11 @@ public class FastRTckTest extends TruffleTCK {
         "builtinFunctionType <- function() 'builtin'\n" +
         "valueWithSource <- function() intValue\n" +
         "objectWithKeyInfoAttributes <- function() { list(rw=1, invocable=function(){ 'invoked' }) }\n" +
-        "for (name in ls()) export(name, get(name))\n",
-        RSource.Internal.TCK_INIT
-    );
+        "for (name in ls()) export(name, get(name))\n";
     // @formatter:on
 
+    private static final Source INITIALIZATION = Source.newBuilder(INITIALIZATION_CODE).name("TCK").mimeType(RRuntime.R_APP_MIME).build();
+
     @Override
     protected PolyglotEngine prepareVM(Builder builder) throws Exception {
         PolyglotEngine engine = builder.build();
diff --git a/mx.fastr/mx_fastr_pkgs.py b/mx.fastr/mx_fastr_pkgs.py
index a505536eba508fd6134f03d5a50c02deca8d5317..9bd585cc92f0102b39ccf4484898302e0b6b1d39 100644
--- a/mx.fastr/mx_fastr_pkgs.py
+++ b/mx.fastr/mx_fastr_pkgs.py
@@ -434,7 +434,7 @@ def _set_test_status(fastr_test_info):
             with open(fastr_testfile_status.abspath) as f:
                 fastr_content = f.readlines()
 
-            result = _fuzzy_compare(gnur_content, fastr_content)
+            result = _fuzzy_compare(gnur_content, fastr_content, gnur_testfile_status.abspath, fastr_testfile_status.abspath)
             if result == -1:
                 print "{0}: content malformed: {1}".format(pkg, gnur_test_output_relpath)
                 fastr_test_status.status = "INDETERMINATE"
@@ -503,9 +503,14 @@ def _find_line(gnur_line, fastr_content, fastr_i):
 
 def _replace_engine_references(output):
     for idx, val in enumerate(output):
-        output[idx] = val.replace('fastr', '<engine>').replace('gnur', '<engine>')
-
-def _fuzzy_compare(gnur_content, fastr_content):
+        if "RUNIT TEST PROTOCOL -- " in val:
+            # RUnit prints the current date and time
+            output[idx] = "RUNIT TEST PROTOCOL -- <date/time>"
+        else:
+            # ignore differences which come from test directory paths
+            output[idx] = val.replace('fastr', '<engine>').replace('gnur', '<engine>')
+
+def _fuzzy_compare(gnur_content, fastr_content, gnur_filename, fastr_filename):
     _replace_engine_references(gnur_content)
     _replace_engine_references(fastr_content)
     gnur_start = _find_start(gnur_content)
@@ -525,15 +530,31 @@ def _fuzzy_compare(gnur_content, fastr_content):
 
         fastr_line = fastr_content[fastr_i]
         if gnur_line != fastr_line:
+            if fastr_line.startswith('Warning') and 'FastR does not support graphics package' in fastr_content[fastr_i + 1]:
+                # ignore warning about FastR not supporting the graphics package
+                fastr_i = fastr_i + 2
+                if fastr_content[fastr_i].startswith('NULL') and not gnur_line.startswith('NULL'):
+                    # ignore additional visible NULL
+                    fastr_i = fastr_i + 1
+                continue
+            if gnur_line.startswith('Warning') and gnur_i + 1 < gnur_end and 'closing unused connection' in gnur_content[gnur_i + 1]:
+                # ignore message about closed connection
+                gnur_i = gnur_i + 2
+                continue
+            if gnur_i > 0 and gnur_content[gnur_i - 1].startswith('   user  system elapsed'):
+                # ignore differences in timing
+                gnur_i = gnur_i + 1
+                fastr_i = fastr_i + 1
+                continue
             # we are fuzzy on Error/Warning as FastR often differs
             # in the context/format of the error/warniong message AND GnuR is sometimes
             # inconsistent over which error message it uses. Unlike the unit test environment,
             # we cannot tag tests in any way, so we simply check that FastR does report
             # an error. We then scan forward to try to get the files back in sync, as the
             # the number of error/warning lines may differ.
-            if gnur_line.startswith(('Error', 'Warning')):
-                to_match = 'Error' if gnur_line.startswith('Error') else 'Warning'
-                if not fastr_line.startswith(to_match):
+            if 'Error' in gnur_line or 'Warning' in gnur_line:
+                to_match = 'Error' if 'Error' in gnur_line else 'Warning'
+                if to_match not in fastr_line:
                     result = 1
                     break
                 else:
@@ -562,6 +583,11 @@ def _fuzzy_compare(gnur_content, fastr_content):
                     break
         gnur_i = gnur_i + 1
         fastr_i = fastr_i + 1
+    if result == 1:
+        print gnur_filename + ':%d' % gnur_i + ' vs. ' + fastr_filename + ':%d' % fastr_i
+        print gnur_line.strip()
+        print "vs."
+        print fastr_line.strip()
     return result
 
 def _ignore_whitespace(gnur_line, fastr_line):
@@ -572,7 +598,7 @@ def pkgtest_cmp(args):
         gnur_content = f.readlines()
     with open(args[1]) as f:
         fastr_content = f.readlines()
-    return _fuzzy_compare(gnur_content, fastr_content)
+    return _fuzzy_compare(gnur_content, fastr_content, args[0], args[1])
 
 def find_top100(args):
     libinstall = join(_fastr_suite_dir(), "top100.tmp")