Enable the workaround for the Loongson 2F bug by default.

Patch by Mark H Weaver <mhw@netris.org>.

--- binutils/gas/config/tc-mips.c.orig	2012-09-04 10:21:03.000000000 -0400
+++ binutils/gas/config/tc-mips.c	2013-10-06 02:23:21.651983768 -0400
@@ -910,10 +910,10 @@
 };
 
 /* ...likewise -mfix-loongson2f-jump.  */
-static bfd_boolean mips_fix_loongson2f_jump;
+static bfd_boolean mips_fix_loongson2f_jump = FALSE;
 
 /* ...likewise -mfix-loongson2f-nop.  */
-static bfd_boolean mips_fix_loongson2f_nop;
+static bfd_boolean mips_fix_loongson2f_nop = TRUE;
 
 /* True if -mfix-loongson2f-nop or -mfix-loongson2f-jump passed.  */
 static bfd_boolean mips_fix_loongson2f;
--- binutils/gas/testsuite/gas/mips/mips.exp.orig	2012-09-04 10:17:13.000000000 -0400
+++ binutils/gas/testsuite/gas/mips/mips.exp	2013-10-06 02:23:21.663983768 -0400
@@ -91,6 +91,12 @@
 
     # Catch because the variable won't be set the first time through.
     catch {unset mips_arches}
+
+    # Disable the loongson2f nop fix by default, because most of the
+    # existing test cases for mips will fail otherwise.
+    global ASFLAGS
+    set old_ASFLAGS "$ASFLAGS"
+    set ASFLAGS "$ASFLAGS -mno-fix-loongson2f-nop"
 }
 
 # mips_arch_create ARCH GPRSIZE EXTENDS PROPS AS_FLAGS OBJDUMP_FLAGS \
cripts?id=4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9'>commit</a><a href='/guix/diff/scripts?id=4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/scripts'>
<input type='hidden' name='id' value='4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9'>root</a>/<a href='/guix/log/scripts?id=4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9'>scripts</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/scripts?id=4eb6ed28a3b62ffe0fca2a9924fd68cc917ea6b9&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>