fixes to gcc_jit_context_dump_reproducer_to_file

gcc/jit/ChangeLog:
	* jit-recording.c
	(gcc::jit::recording::context::dump_reproducer_to_file):
	Add pragma to generated reproducers to disable -Wunused-variable.
	Fix handling of NULL string options.

From-SVN: r225204

gcc/jit/ChangeLog

 2015-06-30  David Malcolm  <dmalcolm@redhat.com>
 
+	* jit-recording.c
+	(gcc::jit::recording::context::dump_reproducer_to_file):
+	Add pragma to generated reproducers to disable -Wunused-variable.
+	Fix handling of NULL string options.
+
+2015-06-30  David Malcolm  <dmalcolm@redhat.com>
+
 	* docs/cp/topics/expressions.rst: Remove stray semicolon.
 	* docs/cp/topics/functions.rst: Remove stray backslash.
 	* docs/_build/texinfo/libgccjit.texi: Regenerate.

gcc/jit/jit-recording.c

@@ -1494,6 +1494,7 @@ recording::context::dump_reproducer_to_file (const char *path)
   print_version (r.get_file (), "  ", false);
   r.write ("*/\n");
   r.write ("#include <libgccjit.h>\n\n");
+  r.write ("#pragma GCC diagnostic ignored \"-Wunused-variable\"\n\n");
   r.write ("static void\nset_options (");
   r.write_params (contexts);
   r.write (");\n\n");
@@ -1564,12 +1565,17 @@ recording::context::dump_reproducer_to_file (const char *path)
 
       r.write ("  /* String options.  */\n");
       for (int opt_idx = 0; opt_idx < GCC_JIT_NUM_STR_OPTIONS; opt_idx++)
-	r.write ("  gcc_jit_context_set_str_option (%s,\n"
-		 "                                  %s,\n"
-		 "                                  \"%s\");\n",
-		 r.get_identifier (contexts[ctxt_idx]),
-		 str_option_reproducer_strings[opt_idx],
-		 m_str_options[opt_idx] ? m_str_options[opt_idx] : "NULL");
+	{
+	  r.write ("  gcc_jit_context_set_str_option (%s,\n"
+		   "                                  %s,\n",
+		   r.get_identifier (contexts[ctxt_idx]),
+		   str_option_reproducer_strings[opt_idx]);
+	  if (m_str_options[opt_idx])
+	    r.write ("                                  \"%s\");\n",
+		     m_str_options[opt_idx]);
+	  else
+	    r.write ("                                  NULL);\n");
+	}
       r.write ("  /* Int options.  */\n");
       for (int opt_idx = 0; opt_idx < GCC_JIT_NUM_INT_OPTIONS; opt_idx++)
 	r.write ("  gcc_jit_context_set_int_option (%s,\n"