Warn to not add debug hook targets

This adds a boiler-plate warning to the debug hooks structure to
strongly discourage people from adding new debug hook targets since
we want to get rid of the current abstraction in favor of maintaining
a DWARF view of debug in the middle-end and have support for alternate
output formats to be generated off that DWARF representation.

2021-03-22  Richard Biener  <rguenther@suse.de>

	* debug.h: Add deprecation warning.

diff --git a/gcc/debug.h b/gcc/debug.h
index 67e5267..cd265ff 100644 (file)
--- a/gcc/debug.h
+++ b/gcc/debug.h
@@ -21,6 +21,10 @@
 /* This structure contains hooks for the debug information output
    functions, accessed through the global instance debug_hooks set in
    toplev.c according to command line options.  */
+/* WARNING: Do not add new debug hook targets - DWARF will be the only
+   way to speak debug to the middle-end once we are able to get rid of
+   the remaining targets.  If you need alternate output formats instead
+   generate them off the DWARF representation.  */
 struct gcc_debug_hooks
 {
   /* Initialize debug output.  MAIN_FILENAME is the name of the main