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| author | Nathan Sidwell <nathan@acm.org> | 2020-11-24 08:23:55 -0800 |
|---|---|---|
| committer | Nathan Sidwell <nathan@acm.org> | 2020-11-24 08:31:03 -0800 |
| commit | 13f93cf5336ec0085277b9a5ef88c02359527170 (patch) | |
| tree | 21dd731e4de98eaab84f2e61d5bc54debf9c9851 /libcpp/directives.c | |
| parent | 489be3119e6cd092bf7f30880a5d641f0bf0672f (diff) | |
| download | gcc-13f93cf5336ec0085277b9a5ef88c02359527170.zip gcc-13f93cf5336ec0085277b9a5ef88c02359527170.tar.gz gcc-13f93cf5336ec0085277b9a5ef88c02359527170.tar.bz2 | |
preprocessor: Add deferred macros
Deferred macros are needed for C++ modules. Header units may export
macro definitions and undefinitions. These are resolved lazily at the
point of (potential) use. (The language specifies that, it's not just
a useful optimization.) Thus, identifier nodes grow a 'deferred'
field, which fortunately doesn't expand the structure on 64-bit
systems as there was padding there. This is non-zero on NT_MACRO
nodes, if the macro is deferred. When such an identifier is lexed, it
is resolved via a callback that I added recently. That will either
provide the macro definition, or discover it there was an overriding
undef. Either way the identifier is no longer a deferred macro.
Notice it is now possible for NT_MACRO nodes to have a NULL macro
expansion.
libcpp/
* include/cpplib.h (struct cpp_hashnode): Add deferred field.
(cpp_set_deferred_macro): Define.
(cpp_get_deferred_macro): Declare.
(cpp_macro_definition): Reformat, add overload.
(cpp_macro_definition_location): Deal with deferred macro.
(cpp_alloc_token_string, cpp_compare_macro): Declare.
* internal.h (_cpp_notify_macro_use): Return bool
(_cpp_maybe_notify_macro_use): Likewise.
* directives.c (do_undef): Check macro is not undef before
warning.
(do_ifdef, do_ifndef): Deal with deferred macro.
* expr.c (parse_defined): Likewise.
* lex.c (cpp_allocate_token_string): Break out of ...
(create_literal): ... here. Call it.
(cpp_maybe_module_directive): Deal with deferred macro.
* macro.c (cpp_get_token_1): Deal with deferred macro.
(warn_of_redefinition): Deal with deferred macro.
(compare_macros): Rename to ...
(cpp_compare_macro): ... here. Make extern.
(cpp_get_deferred_macro): New.
(_cpp_notify_macro_use): Deal with deferred macro, return bool
indicating definedness.
(cpp_macro_definition): Deal with deferred macro.
Diffstat (limited to 'libcpp/directives.c')
| -rw-r--r-- | libcpp/directives.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/libcpp/directives.c b/libcpp/directives.c index bffdc91..fa66b5c 100644 --- a/libcpp/directives.c +++ b/libcpp/directives.c @@ -667,7 +667,8 @@ do_undef (cpp_reader *pfile) pfile->directive_line, 0, "undefining \"%s\"", NODE_NAME (node)); - if (CPP_OPTION (pfile, warn_unused_macros)) + if (node->value.macro + && CPP_OPTION (pfile, warn_unused_macros)) _cpp_warn_if_unused_macro (pfile, node, NULL); _cpp_free_definition (node); @@ -1981,8 +1982,10 @@ do_ifdef (cpp_reader *pfile) if (node) { skip = !_cpp_defined_macro_p (node); + if (!_cpp_maybe_notify_macro_use (pfile, node, pfile->directive_line)) + /* It wasn't a macro after all. */ + skip = true; _cpp_mark_macro_used (node); - _cpp_maybe_notify_macro_use (pfile, node, pfile->directive_line); if (pfile->cb.used) pfile->cb.used (pfile, pfile->directive_line, node); check_eol (pfile, false); @@ -2006,8 +2009,10 @@ do_ifndef (cpp_reader *pfile) if (node) { skip = _cpp_defined_macro_p (node); + if (!_cpp_maybe_notify_macro_use (pfile, node, pfile->directive_line)) + /* It wasn't a macro after all. */ + skip = false; _cpp_mark_macro_used (node); - _cpp_maybe_notify_macro_use (pfile, node, pfile->directive_line); if (pfile->cb.used) pfile->cb.used (pfile, pfile->directive_line, node); check_eol (pfile, false); |