* Makefile.in (c-exp.tab.c, m2-exp.tab.c): Add sed patterns to

remap all malloc's to xmalloc's and all realloc's to xrealloc's.
	* c-exp.y, m2-exp.y:  Add comment about how malloc/realloc are
	  remapped to xmalloc/xrealloc, use only malloc/realloc in grammer
	  file.  Remove preprocessor defines that previously did remapping.

gdb/c-exp.y

@@ -24,7 +24,15 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
    See expression.h for the details of the format.
    What is important here is that it can be built up sequentially
    during the process of parsing; the lower levels of the tree always
-   come first in the result.  */
+   come first in the result.
+
+   Note that malloc's and realloc's in this file are transformed to
+   xmalloc and xrealloc respectively by the same sed command in the
+   makefile that remaps any other malloc/realloc inserted by the parser
+   generator.  Doing this with #defines and trying to control the interaction
+   with include files (<malloc.h> and <stdlib.h> for example) just became
+   too messy, particularly when such includes can be inserted at random
+   times by the parser generator.  */
    
 %{
 
@@ -193,18 +201,6 @@ parse_number PARAMS ((char *, int, int, YYSTYPE *));
 %type <bval> block
 %left COLONCOLON
 
-%{
-/* Ensure that if the generated parser contains any calls to malloc/realloc,
-   that they get mapped to xmalloc/xrealloc.  We have to do this here
-   rather than earlier in the file because this is the first point after
-   the place where the SVR4 yacc includes <malloc.h>, and if we do it
-   before that, then the remapped declarations in <malloc.h> will collide
-   with the ones in "defs.h". */
-
-#define malloc	xmalloc
-#define realloc	xrealloc
-%}
-
 
 %%
 
@@ -913,13 +909,13 @@ typename:	TYPENAME
 
 nonempty_typelist
 	:	type
-		{ $$ = (struct type **) xmalloc (sizeof (struct type *) * 2);
+		{ $$ = (struct type **) malloc (sizeof (struct type *) * 2);
 		  $<ivec>$[0] = 1;	/* Number of types in vector */
 		  $$[1] = $1;
 		}
 	|	nonempty_typelist ',' type
 		{ int len = sizeof (struct type *) * (++($<ivec>1[0]) + 1);
-		  $$ = (struct type **) xrealloc ((char *) $1, len);
+		  $$ = (struct type **) realloc ((char *) $1, len);
 		  $$[$<ivec>$[0]] = $3;
 		}
 	;