As shown by Roger Orr in the comments of this PR, cpp_get_token can
cause a reallocation that invalidates some of the variables in
do_linemarker. It seems to occur in this call to linemap_add:
/* Allocate the new line_map. However, if the current map only has a
single line we can sometimes just increase its column_bits instead. */
if (line_delta < 0
|| last_line != ORDINARY_MAP_STARTING_LINE_NUMBER (map)
|| SOURCE_COLUMN (map, highest) >= (1U << column_bits)
|| range_bits < map->m_range_bits)
map = linemap_check_ordinary
(const_cast <line_map *>
(linemap_add (set, LC_RENAME,
ORDINARY_MAP_IN_SYSTEM_HEADER_P (map),
ORDINARY_MAP_FILE_NAME (map),
to_line)));
I'm still not very familiar with this code, but I believe with LC_RENAME
we'll retain the right information in INCLUDED_FROM even if map changes.
I've put his patch, slightly adapted, through a bootstrap and test cycle
on x86_64-linux. Ok to apply?
Bernd
PR preprocessor/69650
* directives.c (do_linemarker): Reread map after calling
cpp_get_token.
Index: libcpp/directives.c
===================================================================
--- libcpp/directives.c (revision 234831)
+++ libcpp/directives.c (working copy)
@@ -1048,6 +1048,9 @@ do_linemarker (cpp_reader *pfile)
if (reason == LC_LEAVE)
{
+ /* Reread map since cpp_get_token can invalidate it with a
+ reallocation. */
+ map = LINEMAPS_LAST_ORDINARY_MAP (line_table);
const line_map_ordinary *from;
if (MAIN_FILE_P (map)
|| (new_file
@@ -1055,7 +1058,8 @@ do_linemarker (cpp_reader *pfile)
&& filename_cmp (ORDINARY_MAP_FILE_NAME (from), new_file) != 0))
{
cpp_warning (pfile, CPP_W_NONE,
- "file \"%s\" linemarker ignored due to incorrect nesting", new_file);
+ "file \"%s\" linemarker ignored due to "
+ "incorrect nesting", new_file);
return;
}
}
