PR preprocessor/69985: fix ICE with long lines in -Wformat

gcc/testsuite/ChangeLog:
	PR preprocessor/69985
	* gcc.dg/cpp/pr69985.c: New test case.

libcpp/ChangeLog:
	PR preprocessor/69985
	(linemap_position_for_loc_and_offset): Rename param from "offset"
	to "column_offset".  Right-shift the column_offset by m_range_bits
	of the pertinent ordinary map whenever offsetting a
	source_location.  For clarity, offset the column by the column
	offset, rather than the other way around.

From-SVN: r233836

gcc/testsuite/ChangeLog

+2016-02-29  David Malcolm  <dmalcolm@redhat.com>
+
+	PR preprocessor/69985
+	* gcc.dg/cpp/pr69985.c: New test case.
+
 2016-02-29  Jeff Law  <law@redhat.com>
 
 	PR tree-optimization/70005

gcc/testsuite/gcc.dg/cpp/pr69985.c

+/* { dg-options "-Wformat" } */
+extern int printf (const char *__restrict __format, ...);
+void test (void)
+{
+  /* A very long line, so that we start a new line map.  */
+  printf ("%llu01233456789012334567890123345678901233456789012334567890123345678901233456789012334567890123345678901233456789012334567890123345678901233456789"); /* { dg-warning "15: format .%llu. expects a matching" } */
+}

libcpp/ChangeLog

+2016-02-29  David Malcolm  <dmalcolm@redhat.com>
+
+	PR preprocessor/69985
+	(linemap_position_for_loc_and_offset): Rename param from "offset"
+	to "column_offset".  Right-shift the column_offset by m_range_bits
+	of the pertinent ordinary map whenever offsetting a
+	source_location.  For clarity, offset the column by the column
+	offset, rather than the other way around.
+
 2016-02-23  David Malcolm  <dmalcolm@redhat.com>
 
 	PR preprocessor/69126

libcpp/line-map.c

@@ -864,13 +864,13 @@ linemap_position_for_line_and_column (line_maps *set,
 }
 
 /* Encode and return a source_location starting from location LOC and
-   shifting it by OFFSET columns.  This function does not support
+   shifting it by COLUMN_OFFSET columns.  This function does not support
    virtual locations.  */
 
 source_location
 linemap_position_for_loc_and_offset (struct line_maps *set,
 				     source_location loc,
-				     unsigned int offset)
+				     unsigned int column_offset)
 {
   const line_map_ordinary * map = NULL;
 
@@ -882,7 +882,7 @@ linemap_position_for_loc_and_offset (struct line_maps *set,
       (!linemap_location_from_macro_expansion_p (set, loc)))
     return loc;
 
-  if (offset == 0
+  if (column_offset == 0
       /* Adding an offset to a reserved location (like
 	 UNKNOWN_LOCATION for the C/C++ FEs) does not really make
 	 sense.  So let's leave the location intact in that case.  */
@@ -894,7 +894,7 @@ linemap_position_for_loc_and_offset (struct line_maps *set,
   /* The new location (loc + offset) should be higher than the first
      location encoded by MAP.  This can fail if the line information
      is messed up because of line directives (see PR66415).  */
-  if (MAP_START_LOCATION (map) >= loc + offset)
+  if (MAP_START_LOCATION (map) >= loc + (column_offset << map->m_range_bits))
     return loc;
 
   linenum_type line = SOURCE_LINE (map, loc);
@@ -905,7 +905,8 @@ linemap_position_for_loc_and_offset (struct line_maps *set,
      the next line map of the set.  Otherwise, we try to encode the
      location in the next map.  */
   while (map != LINEMAPS_LAST_ORDINARY_MAP (set)
-	 && loc + offset >= MAP_START_LOCATION (&map[1]))
+	 && (loc + (column_offset << map->m_range_bits)
+	     >= MAP_START_LOCATION (&map[1])))
     {
       map = &map[1];
       /* If the next map starts in a higher line, we cannot encode the
@@ -914,12 +915,12 @@ linemap_position_for_loc_and_offset (struct line_maps *set,
 	return loc;
     }
 
-  offset += column;
-  if (linemap_assert_fails (offset < (1u << map->m_column_and_range_bits)))
+  column += column_offset;
+  if (linemap_assert_fails (column < (1u << map->m_column_and_range_bits)))
     return loc;
 
   source_location r = 
-    linemap_position_for_line_and_column (set, map, line, offset);
+    linemap_position_for_line_and_column (set, map, line, column);
   if (linemap_assert_fails (r <= set->highest_location)
       || linemap_assert_fails (map == linemap_lookup (set, r)))
     return loc;