C++: provide macro used-before-defined hint (PR c++/72786)
This patch uses the name_hint/deferred_diagnostic to provide
a message in the C++ frontend if a macro is used before it is defined
e.g.:
test.c:6:24: error: expected ';' at end of member declaration
virtual void clone() const OVERRIDE { }
^~~~~
;
test.c:6:30: error: 'OVERRIDE' does not name a type
virtual void clone() const OVERRIDE { }
^~~~~~~~
test.c:6:30: note: the macro 'OVERRIDE' had not yet been defined
test.c:15:0: note: it was later defined here
#define OVERRIDE override
It's possible to do it from the C++ frontend as tokenization happens
up-front (and hence the macro already exists when the above is parsed);
I attempted to do it from the C frontend, but because the C frontend only
tokenizes on-demand during parsing, the macro isn't known about until
later.
gcc/cp/ChangeLog:
PR c++/72786
* name-lookup.c (class macro_use_before_def): New class.
(lookup_name_fuzzy): Detect macro that were used before being
defined, and report them as such.
gcc/ChangeLog:
PR c++/72786
* spellcheck.h (best_match::blithely_get_best_candidate): New
accessor.
gcc/testsuite/ChangeLog:
PR c++/72786
* g++.dg/spellcheck-macro-ordering-2.C: New test case.
* g++.dg/spellcheck-macro-ordering.C: Add dg-message directives
for macro used-before-defined.
libcpp/ChangeLog:
PR c++/72786
* include/cpplib.h (cpp_macro_definition_location): New decl.
* macro.c (cpp_macro_definition): New function.
From-SVN: r254978
diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h
index 101b33a..4d04a48 100644
--- a/libcpp/include/cpplib.h
+++ b/libcpp/include/cpplib.h
@@ -889,6 +889,7 @@
extern bool cpp_fun_like_macro_p (cpp_hashnode *);
extern const unsigned char *cpp_macro_definition (cpp_reader *,
cpp_hashnode *);
+extern source_location cpp_macro_definition_location (cpp_hashnode *);
extern void _cpp_backup_tokens (cpp_reader *, unsigned int);
extern const cpp_token *cpp_peek_token (cpp_reader *, int);