@@ -318,6 +318,7 @@ c_common_read_pch (cpp_reader *pfile, const char *name,
struct save_macro_data *smd;
expanded_location saved_loc;
bool saved_trace_includes;
+ int cpp_result;
timevar_push (TV_PCH_RESTORE);
@@ -343,20 +344,26 @@ c_common_read_pch (cpp_reader *pfile, const char *name,
cpp_set_line_map (pfile, line_table);
rebuild_location_adhoc_htab (line_table);
line_table->trace_includes = saved_trace_includes;
- linemap_add (line_table, LC_ENTER, 0, saved_loc.file, saved_loc.line);
+
+ /* Set the current location to the line containing the #include (or the
+ #pragma GCC pch_preprocess) for the purpose of assigning locations to any
+ macros that are about to be restored. */
+ linemap_add (line_table, LC_ENTER, 0, saved_loc.file,
+ saved_loc.line > 1 ? saved_loc.line - 1 : saved_loc.line);
timevar_push (TV_PCH_CPP_RESTORE);
- if (cpp_read_state (pfile, name, f, smd) != 0)
- {
- fclose (f);
- timevar_pop (TV_PCH_CPP_RESTORE);
- goto end;
- }
- timevar_pop (TV_PCH_CPP_RESTORE);
+ cpp_result = cpp_read_state (pfile, name, f, smd);
+ /* Set the current location to the line following the #include, where we
+ were prior to processing the PCH. */
+ linemap_line_start (line_table, saved_loc.line, 0);
+ timevar_pop (TV_PCH_CPP_RESTORE);
fclose (f);
+ if (cpp_result != 0)
+ goto end;
+
/* Give the front end a chance to take action after a PCH file has
been loaded. */
if (lang_post_pch_load)
@@ -838,7 +838,14 @@ cpp_read_state (cpp_reader *r, const char *name, FILE *f,
!= NULL)
{
_cpp_clean_line (r);
- if (!_cpp_create_definition (r, h, 0))
+
+ /* ??? Using r->line_table->highest_line is not ideal here, but we
+ do need to use some location that is relative to the new line
+ map just loaded, not the old one that was in effect when these
+ macros were lexed. The proper fix is to remember the file name
+ and line number where each macro was defined, and then add
+ these locations into the new line map. See PR105608. */
+ if (!_cpp_create_definition (r, h, r->line_table->highest_line))
abort ();
_cpp_pop_buffer (r);
}
This backport for gcc-13 is the second of two required for the g++.dg/pch/line-map-3.C test to stop hitting a variant of the known problem mentioned in that testcase: on riscv64-elf and riscv32-elf, after restoring the PCH, the location of the macros is mentioned as if they were on line 3 rather than 2, so even the existing xfails fail. I think this might be too much to backport, and I'm ready to use an xfail instead, but since this would bring more predictability, I thought I'd ask whether you'd find this backport acceptable. Regstrapped on x86_64-linux-gnu, along with other backports, and tested manually on riscv64-elf. Ok to install? From: Lewis Hyatt <lhyatt@gmail.com> libcpp currently lacks the infrastructure to assign correct locations to macros that were defined prior to loading a PCH and then restored afterwards. While I plan to address that fully for GCC 15, this patch improves things by using at least a valid location, even if it's not the best one. Without this change, libcpp uses pfile->directive_line as the location for the restored macros, but this location_t applies to the old line map, not the one that was just restored from the PCH, so the resulting location is unpredictable and depends on what was stored in the line maps before. With this change, all restored macros get assigned locations at the line of the #include that triggered the PCH restore. A future patch will store the actual file name and line number of each definition and then synthesize locations in the new line map pointing to the right place. gcc/c-family/ChangeLog: PR preprocessor/105608 * c-pch.cc (c_common_read_pch): Adjust line map so that libcpp assigns a location to restored macros which is the same location that triggered the PCH include. libcpp/ChangeLog: PR preprocessor/105608 * pch.cc (cpp_read_state): Set a valid location for restored macros. (cherry picked from commit 019dc63819befb2b82077fb2d76b5dd670946f36) --- gcc/c-family/c-pch.cc | 23 +++++++++++++++-------- libcpp/pch.cc | 9 ++++++++- 2 files changed, 23 insertions(+), 9 deletions(-)