libcpp: Improve location for macro names [PR66290]

When libcpp reports diagnostics whose locus is a macro name (such as for
-Wunused-macros), it uses the location in the cpp_macro object that was
stored by _cpp_new_macro. This is currently set to pfile->directive_line,
which contains the line number only and no column information. This patch
changes the stored location to the src_loc for the token defining the macro
name, which includes the location and range information.

libcpp/ChangeLog:

	PR c++/66290
	* macro.cc (_cpp_create_definition): Add location argument.
	* internal.h (_cpp_create_definition): Adjust prototype.
	* directives.cc (do_define): Pass new location argument to
	_cpp_create_definition.
	(do_undef): Stop passing inferior location to cpp_warning_with_line;
	the default from cpp_warning is better.
	(cpp_pop_definition): Pass new location argument to
	_cpp_create_definition.
	* pch.cc (cpp_read_state): Likewise.

gcc/testsuite/ChangeLog:

	PR c++/66290
	* c-c++-common/cpp/macro-ranges.c: New test.
	* c-c++-common/cpp/line-2.c: Adapt to check for column information
	on macro-related libcpp warnings.
	* c-c++-common/cpp/line-3.c: Likewise.
	* c-c++-common/cpp/macro-arg-count-1.c: Likewise.
	* c-c++-common/cpp/pr58844-1.c: Likewise.
	* c-c++-common/cpp/pr58844-2.c: Likewise.
	* c-c++-common/cpp/warning-zero-location.c: Likewise.
	* c-c++-common/pragma-diag-14.c: Likewise.
	* c-c++-common/pragma-diag-15.c: Likewise.
	* g++.dg/modules/macro-2_d.C: Likewise.
	* g++.dg/modules/macro-4_d.C: Likewise.
	* g++.dg/modules/macro-4_e.C: Likewise.
	* g++.dg/spellcheck-macro-ordering.C: Likewise.
	* gcc.dg/builtin-redefine.c: Likewise.
	* gcc.dg/cpp/Wunused.c: Likewise.
	* gcc.dg/cpp/redef2.c: Likewise.
	* gcc.dg/cpp/redef3.c: Likewise.
	* gcc.dg/cpp/redef4.c: Likewise.
	* gcc.dg/cpp/ucnid-11-utf8.c: Likewise.
	* gcc.dg/cpp/ucnid-11.c: Likewise.
	* gcc.dg/cpp/undef2.c: Likewise.
	* gcc.dg/cpp/warn-redefined-2.c: Likewise.
	* gcc.dg/cpp/warn-redefined.c: Likewise.
	* gcc.dg/cpp/warn-unused-macros-2.c: Likewise.
	* gcc.dg/cpp/warn-unused-macros.c: Likewise.

1 files changed, 10 insertions, 2 deletions

diff --git a/libcpp/macro.cc b/libcpp/macro.cc
index d4238d4..dada8fe 100644
--- a/libcpp/macro.cc
+++ b/libcpp/macro.cc
@@ -3819,7 +3819,8 @@ _cpp_new_macro (cpp_reader *pfile, cpp_macro_kind kind, void *placement)
 
 /* Parse a macro and save its expansion.  Returns nonzero on success.  */
 bool
-_cpp_create_definition (cpp_reader *pfile, cpp_hashnode *node)
+_cpp_create_definition (cpp_reader *pfile, cpp_hashnode *node,
+			location_t name_loc)
 {
   cpp_macro *macro;
 
@@ -3831,6 +3832,13 @@ _cpp_create_definition (cpp_reader *pfile, cpp_hashnode *node)
   if (!macro)
     return false;
 
+  /* _cpp_new_macro () has set macro->line to pfile->directive_line, which
+     denotes the line containing the #define with no column information.  If
+     provided, change to name_loc, which will be the token src_loc for the
+     macro name, including the location and range information.  */
+  if (name_loc)
+    macro->line = name_loc;
+
   if (cpp_macro_p (node))
     {
       if (CPP_OPTION (pfile, warn_unused_macros))
@@ -3844,7 +3852,7 @@ _cpp_create_definition (cpp_reader *pfile, cpp_hashnode *node)
 
 	  bool warned = 
 	    cpp_pedwarning_with_line (pfile, reason,
-				      pfile->directive_line, 0,
+				      macro->line, 0,
 				      "\"%s\" redefined", NODE_NAME (node));
 
 	  if (warned && cpp_user_macro_p (node))