From 6bf2ff0d52a90acdc54f18c75d1978f6b4de4609 Mon Sep 17 00:00:00 2001 From: Nathan Sidwell Date: Tue, 7 Jul 2020 11:28:59 -0700 Subject: preprocessor: Better line info for & With C++ module header units it becomes important to distinguish between macros defined in forced headers (& commandline & builtins) from those defined in the header file being processed. We weren't making that easy because we treated the builtins and command-line locations somewhat file-like, with incrementing line numbers, and showing them as included from line 1 of the main file. This patch does 3 things: 0) extend the idiom that 'line 0' of a file means 'the file as a whole' 1) builtins and command-line macros are shown as-if included from line zero. 2) when emitting preprocessed output we keep resetting the line number so that re-reading that preprocessed output will get the same set of locations for the command line etc. For instance the new c-c++-common/cpp/line-2.c test, now emits In file included from : ./line-2.h:4:2: error: #error wrong 4 | #error wrong | ^~~~~ line-2.c:3:11: error: macro "bill" passed 1 arguments, but takes just 0 3 | int bill(1); | ^ In file included from : ./line-2.h:3: note: macro "bill" defined here 3 | #define bill() 2 | Before it told you about including from :31. the preprocessed output looks like: ... (There's a new optimization in do_line_marker to stop each of these line markers causing a new line map. We can simply rewind the location, and keep using the same line map.) libcpp/ * directives.c (do_linemarker): Optimize rewinding to line zero. * files.c (_cpp_stack_file): Start on line zero when about to inject headers. (cpp_push_include, cpp_push_default_include): Use highest_line as the location. * include/cpplib.h (cpp_read_main_file): Add injecting parm. * init.c (cpp_read_main_file): Likewise, inform _cpp_stack_file. * internal.h (enum include_type): Add IT_MAIN_INJECT. gcc/c-family/ * c-opts.c (c_common_post_options): Add 'injecting' arg to cpp_read_main_file. (c_finish_options): Add linemap_line_start calls for builtin and cmd maps. Force token position to line_table's highest line. * c-ppoutput.c (print_line_1): Refactor, print line zero. (cb_define): Always increment source line. gcc/testsuite/ * c-c++-common/cpp/line-2.c: New. * c-c++-common/cpp/line-2.h: New. * c-c++-common/cpp/line-3.c: New. * c-c++-common/cpp/line-4.c: New. * c-c++-common/cpp/line-4.h: New. --- libcpp/files.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'libcpp/files.c') diff --git a/libcpp/files.c b/libcpp/files.c index 85c79a1..3d48c38 100644 --- a/libcpp/files.c +++ b/libcpp/files.c @@ -947,7 +947,11 @@ _cpp_stack_file (cpp_reader *pfile, _cpp_file *file, include_type type, pfile->line_table->highest_location--; /* Add line map and do callbacks. */ - _cpp_do_file_change (pfile, LC_ENTER, file->path, 1, sysp); + _cpp_do_file_change (pfile, LC_ENTER, file->path, + /* With preamble injection, start on line zero, so + the preamble doesn't appear to have been + included from line 1. */ + type == IT_MAIN_INJECT ? 0 : 1, sysp); return true; } @@ -1475,7 +1479,8 @@ _cpp_compare_file_date (cpp_reader *pfile, const char *fname, bool cpp_push_include (cpp_reader *pfile, const char *fname) { - return _cpp_stack_include (pfile, fname, false, IT_CMDLINE, 0); + return _cpp_stack_include (pfile, fname, false, IT_CMDLINE, + pfile->line_table->highest_line); } /* Pushes the given file, implicitly included at the start of a @@ -1484,7 +1489,8 @@ cpp_push_include (cpp_reader *pfile, const char *fname) bool cpp_push_default_include (cpp_reader *pfile, const char *fname) { - return _cpp_stack_include (pfile, fname, true, IT_DEFAULT, 0); + return _cpp_stack_include (pfile, fname, true, IT_DEFAULT, + pfile->line_table->highest_line); } /* Do appropriate cleanup when a file INC's buffer is popped off the -- cgit v1.1