From c24757cf75cfb3aa26f5260eb36e1ea4ad82c86f Mon Sep 17 00:00:00 2001 From: dmalcolm Date: Wed, 9 Mar 2016 18:23:27 +0000 Subject: PR c++/70105: prevent nonsensical underline spew for macro expansions diagnostic_show_locus can sometimes do the wrong thing when handling expressions built up from macros. PR c++/70105 (currently marked as a P3 regression) has an example of a diagnostic where over 500 lines of irrelevant source are printed, and underlined, giving >1000 lines of useless spew to stderr. This patch adds extra sanitization to diagnostic-show-locus.c, so that we only attempt to print underlines and secondary locations if such locations are "sufficiently sane" relative to the primary location of a diagnostic. This "sufficiently sane" condition is implemented by a new helper function compatible_locations_p, which requires such locations to have the same macro expansion hierarchy as the primary location, using linemap_macro_map_loc_unwind_toward_spelling, effectively mimicing the expansion performed by LRK_SPELLING_LOCATION. This may be too strong a condition, but it effectively fixes PR c++/70105, without removing any underlines in my testing. Successfully bootstrapped®rtested in combination with the previous patch on x86_64-pc-linux-gnu; adds 15 new PASS results to g++.sum and 4 new PASS results to gcc.sum. gcc/ChangeLog: PR c/68473 PR c++/70105 * diagnostic-show-locus.c (compatible_locations_p): New function. (layout::layout): Sanitize ranges using compatible_locations_p. gcc/testsuite/ChangeLog: PR c/68473 PR c++/70105 * g++.dg/diagnostic/pr70105.C: New test. * gcc.dg/plugin/diagnostic-test-expressions-1.c (foo): New decl. (test_multiple_ordinary_maps): New test function. libcpp/ChangeLog: PR c/68473 PR c++/70105 * line-map.c (linemap_macro_map_loc_unwind_toward_spelling): Move decl... * include/line-map.h (linemap_macro_map_loc_unwind_toward_spelling): ...here, converting from static to extern. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@234088 138bc75d-0d04-0410-961f-82ee72b054a4 --- libcpp/line-map.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'libcpp/line-map.c') diff --git a/libcpp/line-map.c b/libcpp/line-map.c index de6eafcbe9b..1fb634af5bf 100644 --- a/libcpp/line-map.c +++ b/libcpp/line-map.c @@ -54,8 +54,6 @@ static const line_map_macro* linemap_macro_map_lookup (struct line_maps *, source_location); static source_location linemap_macro_map_loc_to_def_point (const line_map_macro *, source_location); -static source_location linemap_macro_map_loc_unwind_toward_spelling -(line_maps *set, const line_map_macro *, source_location); static source_location linemap_macro_map_loc_to_exp_point (const line_map_macro *, source_location); static source_location linemap_macro_loc_to_spelling_point -- cgit v1.2.1