Produce Stabs-in-ELF on IRIX 5 with -no-mdebug

[Rainer Orth <ro at CeBiTec dot Uni-Bielefeld dot DE>]

As reported in GCC PR debug/39104
	
	http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39104
        stabs debug info fails on IRIX 5.3

all -gstabs* testcases in the GCC testsuite currently fail:

$ touch debug.c
$ gcc -gstabs -c debug.c
/var/tmp//ccDaTzn4.s: Assembler messages:
/var/tmp//ccDaTzn4.s:3: Warning: illegal .stabs directive, bad character
[...]

With -v, one sees that gas is invoked like this
$ /vol/gcc/bin/gas-2.20.1 -v -EB -g -no-mdebug -mabi=32 -v -o debug.o debug.s

gcc emits .stab* directives for use with Stabs-in-ELF (thus the
-no-mdebug), but the IRIX 5 binutils are configured to support both
ECOFF (and thus Stabs-in-mdebug for compatibility with IRIX 4) and ELF
(this Stabs-in-ELF).  Unfortunately, gas/config/obj-elf.c isn't able to
deal with ECOFF_DEBUGGING not being a compile-time constant, which is
the case here: gas/config/obj-elf.h has

#define ECOFF_DEBUGGING mips_flag_mdebug

To fix the problem, we need to turn the preprocessor check into a
runtime check, which is exactly what the following patch does.

The gcc testcase now assembles correctly and I could verify with objdump
-g and objdump -s that the .stab/.stabstr sections are created as
expected.  A full GCC mainline bootstrap is currently running.  It will
take about a week to complete.

Ok for mainline and 2.21 branch if that passes?

	Rainer
        

2010-04-18  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	* config/obj-elf.c (elf_generate_asm_lineno): New function.
	(elf_process_stab): New function.
	(elf_format_ops): Always use them as generate_asm_lineno,
	process_stab members.

--- gas/config/obj-elf.c~	Mon Sep 14 13:43:27 2009
+++ gas/config/obj-elf.c	Sun Apr 18 00:34:40 2010
@@ -2351,6 +2351,29 @@
 
 #endif /* SCO_ELF */
 
+static void
+elf_generate_asm_lineno (void)
+{
+#ifdef NEED_ECOFF_DEBUG
+  if (ECOFF_DEBUGGING)
+    ecoff_generate_asm_lineno ();
+#endif
+}
+
+static void
+elf_process_stab (segT sec,
+		  int what,
+		  const char *string,
+		  int type,
+		  int other,
+		  int desc)
+{
+#ifdef NEED_ECOFF_DEBUG
+  if (ECOFF_DEBUGGING)
+    ecoff_stab (sec, what, string, type, other, desc);
+#endif
+}
+
 static int
 elf_separate_stab_sections (void)
 {
@@ -2391,13 +2414,8 @@
   0,	/* s_get_type */
   0,	/* s_set_type */
   elf_copy_symbol_attributes,
-#ifdef NEED_ECOFF_DEBUG
-  ecoff_generate_asm_lineno,
-  ecoff_stab,
-#else
-  0,	/* generate_asm_lineno */
-  0,	/* process_stab */
-#endif
+  elf_generate_asm_lineno,
+  elf_process_stab,
   elf_separate_stab_sections,
   elf_init_stab_section,
   elf_sec_sym_ok_for_reloc,

-- 
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University