Message ID | CAESRpQAQaCfab7eNqzEw0tw8VgLVTbKdKYu9QEB7on9h2TGd-A@mail.gmail.com |
---|---|
State | New |
Headers | show |
PING: https://gcc.gnu.org/ml/gcc-patches/2015-08/msg01373.html On 23 August 2015 at 18:07, Manuel López-Ibáñez <lopezibanez@gmail.com> wrote: > linemap_position_for_loc_and_offset() tries to generate a location_t > encoding a column offset from the current location, for example, point > to a certain character inside a string. This is trivial to do when the > new location "fits within" the map of the original location. However, > it may happen that the (long) line corresponding to the original > location is encoded in several maps, thus the new location should > actually be encoded in a subsequent map from the original location. > This patch detects this case and adjusts the map correspondingly. > > (This shows that the line-map representation is quite wasteful in this > case, because line-maps always start at column 0. That is, map[0] > highest location may encode up to line 8 column 80, then > map[1]->start_location starts encoding at line 8 column 0. Thus, there > are two location_t values that point to the same source location.) > > No new testcase since Marek found out this when tackling PR c/66415 > (https://gcc.gnu.org/ml/gcc-patches/2015-06/msg00411.html). This > change just fixes the column number. > > Bootstrapped & regtested on x86-64-linux-gnu. > > OK? > > libcpp/ChangeLog: > > 2015-08-23 Manuel López-Ibáñez <manu@gcc.gnu.org> > > * line-map.c (linemap_position_for_loc_and_offset): Handle the > case of long lines encoded in multiple maps. > > > gcc/testsuite/ChangeLog: > > 2015-08-23 Manuel López-Ibáñez <manu@gcc.gnu.org> > > * gcc.dg/cpp/pr66415-1.c: Test column number.
On Sun, Aug 23, 2015 at 06:07:13PM +0200, Manuel López-Ibáñez wrote: > linemap_position_for_loc_and_offset() tries to generate a location_t > encoding a column offset from the current location, for example, point > to a certain character inside a string. This is trivial to do when the > new location "fits within" the map of the original location. However, > it may happen that the (long) line corresponding to the original > location is encoded in several maps, thus the new location should > actually be encoded in a subsequent map from the original location. > This patch detects this case and adjusts the map correspondingly. > > (This shows that the line-map representation is quite wasteful in this > case, because line-maps always start at column 0. That is, map[0] > highest location may encode up to line 8 column 80, then > map[1]->start_location starts encoding at line 8 column 0. Thus, there > are two location_t values that point to the same source location.) > > No new testcase since Marek found out this when tackling PR c/66415 > (https://gcc.gnu.org/ml/gcc-patches/2015-06/msg00411.html). This > change just fixes the column number. > > Bootstrapped & regtested on x86-64-linux-gnu. > > OK? Ok, thanks. Marek
Index: gcc/testsuite/gcc.dg/cpp/pr66415-1.c =================================================================== --- gcc/testsuite/gcc.dg/cpp/pr66415-1.c (revision 226953) +++ gcc/testsuite/gcc.dg/cpp/pr66415-1.c (working copy) @@ -3,7 +3,7 @@ /* { dg-options "-Wformat" } */ void fn1 (void) { - __builtin_printf ("xxxxxxxxxxxxxxxxx%dxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"); /* { dg-warning "format" } */ + __builtin_printf ("xxxxxxxxxxxxxxxxx%dxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"); /* { dg-warning "71:format" } */ } Index: libcpp/line-map.c =================================================================== --- libcpp/line-map.c (revision 226953) +++ libcpp/line-map.c (working copy) @@ -686,32 +686,38 @@ linemap_position_for_loc_and_offset (str return loc; /* We find the real location and shift it. */ loc = linemap_resolve_location (set, loc, LRK_SPELLING_LOCATION, &map); /* The new location (loc + offset) should be higher than the first - location encoded by MAP. - FIXME: We used to linemap_assert_fails here and in the if below, - but that led to PR66415. So give up for now. */ - if ((MAP_START_LOCATION (map) >= loc + offset)) + 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) return loc; + linenum_type line = SOURCE_LINE (map, loc); + unsigned int column = SOURCE_COLUMN (map, loc); + /* If MAP is not the last line map of its set, then the new location (loc + offset) should be less than the first location encoded by - the next line map of the set. */ - if (map != LINEMAPS_LAST_ORDINARY_MAP (set)) - if ((loc + offset >= MAP_START_LOCATION (&map[1]))) - return loc; + 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])) + { + map = &map[1]; + /* If the next map starts in a higher line, we cannot encode the + location there. */ + if (line < ORDINARY_MAP_STARTING_LINE_NUMBER (map)) + return loc; + } - offset += SOURCE_COLUMN (map, loc); - if (linemap_assert_fails - (offset < (1u << map->column_bits))) + offset += column; + if (linemap_assert_fails (offset < (1u << map->column_bits))) return loc; source_location r = - linemap_position_for_line_and_column (map, - SOURCE_LINE (map, loc), - offset); + linemap_position_for_line_and_column (map, line, offset); if (linemap_assert_fails (r <= set->highest_location) || linemap_assert_fails (map == linemap_lookup (set, r))) return loc; return r;