diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2781c1c0d26..b5be7937566 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+1999-12-29  "Martin v. Loewis" <martin@loewis.home.cs.tu-berlin.de>
+
+	Restore i386 binary compatibility in Dwarf EH info.
+	* config/i386/i386.h (DWARF_FRAME_REGISTERS): Define as 17, the old
+	value of FIRST_PSEUDO_REGISTER.
+	* frame.h (DWARF_FRAME_REGISTERS): Default to FIRST_PSEUDO_REGISTER.
+	(struct frame_state): Use DWARF_FRAME_REGISTERS.
+	* dwarfout.c (output_reg_number): Ditto.
+	* dwarf2out.c (reg_number, expand_builtin_init_dwarf_reg_sizes): Ditto.
+	(DWARF_FRAME_RETURN_COLUMN): Default to DWARF_FRAME_REGISTERS.
 
 1999-12-29  Bruce Korb  <autogen@linuxbox.com>
 
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 7cdfe37bc36..1d911f060d4 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -612,6 +612,11 @@ extern int ix86_arch;
 
 #define FIRST_PSEUDO_REGISTER 19
 
+/* Number of hardware registers that go into the DWARF-2 unwind info.
+   If not defined, equals FIRST_PSEUDO_REGISTER.  */
+
+#define DWARF_FRAME_REGISTERS 17
+
 /* 1 for registers that have pervasive standard uses
    and are not available for the register allocator.
    On the 80386, the stack pointer is such, as is the arg pointer. */
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index fc1b61d472e..f4fae3341a0 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -515,7 +515,7 @@ static void dwarf2out_frame_debug_expr	PROTO((rtx, char *));
 #ifdef PC_REGNUM
 #define DWARF_FRAME_RETURN_COLUMN 	DWARF_FRAME_REGNUM (PC_REGNUM)
 #else
-#define DWARF_FRAME_RETURN_COLUMN 	FIRST_PSEUDO_REGISTER
+#define DWARF_FRAME_RETURN_COLUMN 	DWARF_FRAME_REGISTERS
 #endif
 #endif
 
@@ -566,7 +566,7 @@ reg_number (rtl)
 {
   register unsigned regno = REGNO (rtl);
 
-  if (regno >= FIRST_PSEUDO_REGISTER)
+  if (regno >= DWARF_FRAME_REGISTERS)
     {
       warning ("internal regno botch: regno = %d\n", regno);
       regno = 0;
@@ -587,7 +587,7 @@ expand_builtin_init_dwarf_reg_sizes (address)
   rtx addr = expand_expr (address, NULL_RTX, VOIDmode, 0);
   rtx mem = gen_rtx_MEM (mode, addr);
 
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
+  for (i = 0; i < DWARF_FRAME_REGISTERS; ++i)
     {
       int offset = i * GET_MODE_SIZE (mode);
       int size = GET_MODE_SIZE (reg_raw_mode[i]);
diff --git a/gcc/dwarfout.c b/gcc/dwarfout.c
index 4dda62688c3..f5b0fb5a75b 100644
--- a/gcc/dwarfout.c
+++ b/gcc/dwarfout.c
@@ -1680,7 +1680,7 @@ output_reg_number (rtl)
 {
   register unsigned regno = REGNO (rtl);
 
-  if (regno >= FIRST_PSEUDO_REGISTER)
+  if (regno >= DWARF_FRAME_REGISTERS)
     {
       warning_with_decl (dwarf_last_decl, "internal regno botch: regno = %d\n",
 			 regno);
diff --git a/gcc/frame.h b/gcc/frame.h
index 985416cd180..330277c03f2 100644
--- a/gcc/frame.h
+++ b/gcc/frame.h
@@ -1,6 +1,6 @@
 /* Header file for unwinding stack frames for exception handling.  */
 /* Compile this one with gcc.  */
-/* Copyright (C) 1997, 1998 Free Software Foundation, Inc.
+/* Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
    Contributed by Jason Merrill <jason@cygnus.com>.
 
 This file is part of GNU CC.
@@ -21,16 +21,20 @@ the Free Software Foundation, 59 Temple Place - Suite 330,
 Boston, MA 02111-1307, USA.  */
 
 
+#ifndef DWARF_FRAME_REGISTERS
+#define DWARF_FRAME_REGISTERS FIRST_PSEUDO_REGISTER
+#endif
+
 typedef struct frame_state
 {
   void *cfa;
   void *eh_ptr;
   long cfa_offset;
   long args_size;
-  long reg_or_offset[FIRST_PSEUDO_REGISTER+1];
+  long reg_or_offset[DWARF_FRAME_REGISTERS+1];
   unsigned short cfa_reg;
   unsigned short retaddr_column;
-  char saved[FIRST_PSEUDO_REGISTER+1];
+  char saved[DWARF_FRAME_REGISTERS+1];
 } frame_state;
 
 /* Values for 'saved' above.  */