mirror of
https://github.com/torvalds/linux.git
synced 2024-11-26 14:12:06 +00:00
cc66bca775
This commit decreases 8 shift/reduce conflicts. A certain amount of grammatical ambiguity comes from how to reduce excessive T_EOL tokens. Let's take a look at the example code below: 1 config A 2 bool "a" 3 4 depends on B 5 6 config B 7 def_bool y The line 3 is melt into "config_option_list", but the line 5 can be either a part of "config_option_list" or "common_stmt" by itself. Currently, the lexer converts '\n' to T_EOL verbatim. In Kconfig, a new line works as a statement terminator, but new lines in empty lines are not critical since empty lines (or lines that contain only whitespaces/comments) are just no-op. If the lexer simply discards no-op lines, the parser will not be bothered by excessive T_EOL tokens. Of course, this means we are shifting the complexity from the parser to the lexer, but it is much easier than tackling on shift/reduce conflicts. I introduced the second stage lexer to tweak the behavior. Discard T_EOL if the previous token is T_EOL or T_HELPTEXT. Two T_EOL tokens in a row is meaningless. T_HELPTEXT is a special token that is reduced without T_EOL. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> |
||
|---|---|---|
| .. | ||
| lxdialog | ||
| tests | ||
| .gitignore | ||
| conf.c | ||
| confdata.c | ||
| expr.c | ||
| expr.h | ||
| gconf-cfg.sh | ||
| gconf.c | ||
| gconf.glade | ||
| images.c | ||
| kconf_id.c | ||
| list.h | ||
| lkc_proto.h | ||
| lkc.h | ||
| Makefile | ||
| mconf-cfg.sh | ||
| mconf.c | ||
| menu.c | ||
| merge_config.sh | ||
| nconf-cfg.sh | ||
| nconf.c | ||
| nconf.gui.c | ||
| nconf.h | ||
| preprocess.c | ||
| qconf-cfg.sh | ||
| qconf.cc | ||
| qconf.h | ||
| streamline_config.pl | ||
| symbol.c | ||
| util.c | ||
| zconf.l | ||
| zconf.y | ||