https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81405
--- Comment #5 from David Malcolm <dmalcolm at gcc dot gnu.org> --- Author: dmalcolm Date: Mon Apr 30 15:01:56 2018 New Revision: 259768 URL: https://gcc.gnu.org/viewcvs?rev=259768&root=gcc&view=rev Log: Use char_span for return type of location_get_source_line location_get_source_line returns a const char * that isn't 0-terminated, writing back a length through an int * param. This is error-prone, as all call-sites have to take into account the lack of 0-termination, and respect the length of the buffer. It's cleaner to bundle together this pointer+length state into a class, so this patch does so, reusing the "char_span" class that I introduced in r250187 (as part of the fix for PR c/81405). The patch also adds assertions to all access to the char_span. gcc/c-family/ChangeLog: * c-format.c (get_corrected_substring): Update for location_get_source_line returning a char_span. Use a char_span when handling the prefix of the correction. * c-indentation.c (get_visual_column): Update for location_get_source_line returning a char_span. (get_first_nws_vis_column): Likewise. gcc/ChangeLog: * diagnostic-show-locus.c (layout::layout): Update for location_get_source_line returning a char_span. (struct char_span): Move to input.h. (struct correction): Update for fields in char_span becoming private. (struct source_line): Update for location_get_source_line returning a char_span. (layout::print_line): Likewise. * edit-context.c (edited_file::print_content): Likewise. (edited_file::print_diff_hunk): Likewise. (edited_file::print_run_of_changed_lines): Likewise. (edited_file::get_num_lines): Likewise. (edited_line::edited_line): Likewise. * final.c (asm_show_source): Likewise. * input.c (location_get_source_line): Convert return type from const char * to char_span, losing the final "line_len" param. (dump_location_info): Update for the above. (get_substring_ranges_for_loc): Likewise. Use a char_span when handling the literal within the line. (test_reading_source_line): Update for location_get_source_line returning a char_span. * input.h (class char_span): Move here from diagnostic-show-locus.c, converting from a struct to a class. Make data members private. (char_span::operator bool): New. (char_span::length): New. (char_span::get_buffer): New. (char_span::operator[]): New. (char_span::subspan): Make const. (char_span::xstrdup): New. (location_get_source_line): Convert return type from const char * to char_span, losing the final "line_size" param. gcc/testsuite/ChangeLog: * gcc.dg/plugin/diagnostic_plugin_test_show_locus.c (test_show_locus): Update for location_get_source_line returning a char_span. Use char_span for handling words in the "test_many_nested_locations" fix-it example. Modified: trunk/gcc/ChangeLog trunk/gcc/c-family/ChangeLog trunk/gcc/c-family/c-format.c trunk/gcc/c-family/c-indentation.c trunk/gcc/diagnostic-show-locus.c trunk/gcc/edit-context.c trunk/gcc/final.c trunk/gcc/input.c trunk/gcc/input.h trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.dg/plugin/diagnostic_plugin_test_show_locus.c
