configure.in: New flag --with-dwarf2.

* configure.in: New flag --with-dwarf2.   If set, enables DWARF-2
debugging as default.
* config/tm-dwarf2.h: New file.

[[Split portion of a mixed commit.]]

From-SVN: r24517.2

gcc/ChangeLog

+Wed Jan  6 17:55:19 1999  Robert Lipe  <robertlipe@usa.net>
+
+	* configure.in: New flag --with-dwarf2.   If set, enables DWARF-2
+	debugging as default.
+
+	* config/tm-dwarf2.h: New file.
+
 Wed Jan  6 16:08:54 1999  Jeffrey A Law  (law@cygnus.com)
 
 	* calls.c (special_function_p): New function broken out of

gcc/configure.in

@@ -278,6 +278,11 @@ changequote([,])
   JAVAGC=$enableval,
   JAVAGC=boehm)
 
+AC_ARG_WITH(dwarf2,
+[  --enable-dwarf2	  enable DWARF2 debugging as default.],
+dwarf2="$with_dwarf2",
+dwarf2=no)
+
 # Determine the host, build, and target systems
 AC_CANONICAL_SYSTEM
 
@@ -3430,6 +3435,10 @@ if test x"$tmake_file" = x
 then tmake_file=$cpu_type/t-$cpu_type
 fi
 
+if test x"$dwarf2" = xyes
+then tm_file="tm-dwarf2.h $tm_file"
+fi
+
 if test x$float_format = x
 then float_format=i64
 fi