Re: [PATCH v2 2/2] gas: re-work line number tracking for macros and their expansions

[Jan Beulich <jbeulich@suse.com>]

On 14.12.2022 17:58, Andrew Burgess wrote:
> Anyway, hopefully the reproducer helps track down the problem.

It did indeed. Below the patch that addresses the issue for me,
but before committing I will want to run this through the full set
of tests (after extending the testcase which didn't catch the issue).

Jan

gas: restore Dwarf info generation after macro diagnostic adjustments

While 6fdb723799e2 ("gas: re-work line number tracking for macros and
their expansions") was meant to leave generated Dwarf as is, it really
didn't (and the testcase intended to catch that wasn't covering the case
which broke). Its adjustment to buffer_and_nest() didn't go far enough,
leading to the "linefile" directive inserted at the top to also be
processed later in the PR gas/16908 workaround (which clearly isn't
intended - it's being put there for processing during macro expansion
only). That unnoticed flaw in turn led me to worked around it by a
(suspicious to me already at the time) conditional in as_where().

--- a/gas/input-scrub.c
+++ b/gas/input-scrub.c
@@ -564,9 +564,6 @@ as_where (unsigned int *linep)
 
       do
 	{
-	  if (!saved->is_linefile)
-	    break;
-
 	  if (expansion != expanding_macro)
 	    /* Nothing.  */;
 	  else if (saved->logical_input_file != NULL
--- a/gas/macro.c
+++ b/gas/macro.c
@@ -120,8 +120,7 @@ buffer_and_nest (const char *from, const
   size_t from_len;
   size_t to_len = strlen (to);
   int depth = 1;
-  size_t line_start = ptr->len;
-  size_t more = get_line (ptr);
+  size_t line_start, more;
 
   if (to_len == 4 && strcasecmp (to, "ENDR") == 0)
     {
@@ -147,6 +146,8 @@ buffer_and_nest (const char *from, const
     xfree (linefile);
   }
 
+  line_start = ptr->len;
+  more = get_line (ptr);
   while (more)
     {
       /* Try to find the first pseudo op on the line.  */