diff mbox series

[2/2,gdb/macro] Ignore malformed macro definition complaint for clang

Message ID 20240517104704.3477-2-tdevries@suse.de
State New
Headers
Series [1/2,gdb/macro] Ignore in-file macro definition with 0 line complaint for clang |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_gdb_build--master-aarch64 success Testing passed
linaro-tcwg-bot/tcwg_gdb_build--master-arm success Testing passed
linaro-tcwg-bot/tcwg_gdb_check--master-aarch64 success Testing passed
linaro-tcwg-bot/tcwg_gdb_check--master-arm success Testing passed

Commit Message

Tom de Vries May 17, 2024, 10:47 a.m. UTC 
  With test-case test.c:
...
 #define NOARG
 int main (void) { return 0; }
...
compiled with clang:
...
$ clang test.c -g3 -fdebug-macro
...
we get a complaint:
...
$ gdb -q -batch -iex "set complaints 5" a.out -ex "p main"
During symbol reading: macro debug info contains a malformed macro definition:
`NOARG'
...
and four others from pre-defined defs.

This is because the macro body is defined as "NOARG" instead of "NOARG ".

There's a comment in parse_macro_definition that describes why the space
should be there, quoting the standard.

My guess is that this is just a matter of interpretation.  Either we have
- a name and empty definition, separated by a space, or
- a name and no definition, and therefore no space.

Anyway, this is long-standing and AFAICT intentional behaviour from clang, and
I think it's entirely reasonable, so drop the complaint for clang.

Likewise for '#define ARG(V)'.

Tested on x86_64-linux.
---
 gdb/dwarf2/macro.c                           | 12 +++++++-----
 gdb/testsuite/gdb.dwarf2/clang-cli-macro.exp |  4 ++++
 2 files changed, 11 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/gdb/dwarf2/macro.c b/gdb/dwarf2/macro.c
index 66a40e88d3a..deaad155bef 100644
--- a/gdb/dwarf2/macro.c
+++ b/gdb/dwarf2/macro.c
@@ -103,7 +103,7 @@  consume_improper_spaces (const char *p, const char *body)
 
 static void
 parse_macro_definition (struct macro_source_file *file, int line,
-			const char *body)
+			const char *body, struct dwarf2_cu *cu)
 {
   const char *p;
 
@@ -149,7 +149,8 @@  parse_macro_definition (struct macro_source_file *file, int line,
 	replacement = body + name_len + 1;
       else
 	{
-	  dwarf2_macro_malformed_definition_complaint (body);
+	  if (!producer_is_clang (cu))
+	    dwarf2_macro_malformed_definition_complaint (body);
 	  replacement = body + name_len;
 	}
 
@@ -213,7 +214,8 @@  parse_macro_definition (struct macro_source_file *file, int line,
 	  else if (*p == '\0')
 	    {
 	      /* Complain, but do define it.  */
-	      dwarf2_macro_malformed_definition_complaint (body);
+	      if (!producer_is_clang (cu))
+		dwarf2_macro_malformed_definition_complaint (body);
 	      macro_define_function (file, line, name.c_str (),
 				     argc, (const char **) argv,
 				     p);
@@ -569,7 +571,7 @@  dwarf_decode_macro_bytes (dwarf2_per_objfile *per_objfile,
 			   line, current_file->filename);
 	      }
 	    else if (is_define)
-	      parse_macro_definition (current_file, line, body);
+	      parse_macro_definition (current_file, line, body, cu);
 	    else
 	      {
 		gdb_assert (macinfo_type == DW_MACRO_undef
@@ -633,7 +635,7 @@  dwarf_decode_macro_bytes (dwarf2_per_objfile *per_objfile,
 	      }
 
 	    if (macinfo_type == DW_MACRO_define_strx)
-	      parse_macro_definition (current_file, line, body);
+	      parse_macro_definition (current_file, line, body, cu);
 	    else
 	      macro_undef (current_file, line, body);
 	   }
diff --git a/gdb/testsuite/gdb.dwarf2/clang-cli-macro.exp b/gdb/testsuite/gdb.dwarf2/clang-cli-macro.exp
index fdeaaff5afd..536132f6aa2 100644
--- a/gdb/testsuite/gdb.dwarf2/clang-cli-macro.exp
+++ b/gdb/testsuite/gdb.dwarf2/clang-cli-macro.exp
@@ -75,6 +75,8 @@  Dwarf::assemble $asm_file {
 	    start_file 0 1
 		# A macro defined at line 1 of the main file.
 		define 1 "TWO 2"
+		define 2 "THREE"
+		define 3 "FOUR(ARG)"
 	    end_file
 	    define 0 "ONE 1"
 	}
@@ -97,3 +99,5 @@  if {![runto_main]} {
 
 gdb_test "print TWO" "= 2" "print simple macro"
 gdb_test "print ONE" "= 1" "print defined from CLI"
+gdb_test "info macro THREE" "\r\n#define THREE "
+gdb_test "info macro FOUR" "\r\n[string_to_regexp {#define FOUR(ARG) }]"