[gcc r12-76] aix: Switch AIX configurtion to DWARF2 debugging

[gcc r12-76] aix: Switch AIX configurtion to DWARF2 debugging

[David Edelsohn]

https://gcc.gnu.org/g:6a2f49c6999fa2c7a3a8cb05005d21f8020d674d

commit r12-76-g6a2f49c6999fa2c7a3a8cb05005d21f8020d674d
Author: David Edelsohn <dje.gcc@gmail.com>
Date:   Tue Jan 14 13:12:59 2020 -0500

    aix: Switch AIX configurtion to DWARF2 debugging
    
    This patch is in preparation for removing stabs debugging support from GCC.
    
    The rs6000 configuration files remain somewhat intertwined with the
    stabs debugging support, but the configuration no longer generates
    stabs debugging information.
    
    This patch means that earlier releases (Technology Levels) of AIX 7.1
    and 7.2, prior to DWARF support and fixes, cannot build GCC or support
    GCC.
    
    gcc/ChangeLog:
    
            * config/rs6000/aix71.h (PREFERRED_DEBUGGING_TYPE): Change to
            DWARF2_DEBUG.
            * config/rs6000/aix72.h (PREFERRED_DEBUGGING_TYPE): Same.

Diff:
---
 gcc/config/rs6000/aix71.h | 4 ++--
 gcc/config/rs6000/aix72.h | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/gcc/config/rs6000/aix71.h b/gcc/config/rs6000/aix71.h
index 3612ed2593b..807e260a175 100644
--- a/gcc/config/rs6000/aix71.h
+++ b/gcc/config/rs6000/aix71.h
@@ -272,9 +272,9 @@ extern long long int    atoll(const char *);
 
 #define TARGET_AIX_VERSION 71
 
-/* AIX 7.1 supports DWARF3 debugging, but XCOFF remains the default.  */
+/* AIX 7.1 supports DWARF3+ debugging.  */
 #define DWARF2_DEBUGGING_INFO 1
-#define PREFERRED_DEBUGGING_TYPE XCOFF_DEBUG
+#define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
 #define DEBUG_INFO_SECTION	"0x10000"
 #define DEBUG_LINE_SECTION	"0x20000"
 #define DEBUG_PUBNAMES_SECTION	"0x30000"
diff --git a/gcc/config/rs6000/aix72.h b/gcc/config/rs6000/aix72.h
index d34909283cc..36c5d994439 100644
--- a/gcc/config/rs6000/aix72.h
+++ b/gcc/config/rs6000/aix72.h
@@ -273,9 +273,9 @@ extern long long int    atoll(const char *);
 
 #define TARGET_AIX_VERSION 72
 
-/* AIX 7.2 supports DWARF3 debugging, but XCOFF remains the default.  */
+/* AIX 7.2 supports DWARF3+ debugging.  */
 #define DWARF2_DEBUGGING_INFO 1
-#define PREFERRED_DEBUGGING_TYPE XCOFF_DEBUG
+#define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG
 #define DEBUG_INFO_SECTION	"0x10000"
 #define DEBUG_LINE_SECTION	"0x20000"
 #define DEBUG_PUBNAMES_SECTION	"0x30000"