* frame.h, blockframe.c, stack.c, a29k-tdep.c,

	config/gould/tmp-{pn,np1}.h,
	config/{sparc/tm-sparc.h,pyr/tm-pyr.h,vax/tm-vax.h}: Remove field
	next_frame from struct frame_info.  It has no purpose beyond
	->next->frame and is an artifact from GDB 2.8.

8 files changed, 247 insertions, 217 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index c844b54..42377f8 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,15 @@
+Wed Jul  7 14:30:00 1993  Jim Kingdon  (kingdon@lioth.cygnus.com)
+
+	* config/{rs6000/tm-rs6000.h,sparc/tm-sparc.h,pyr/tm-pyr.h},
+	inferior.h (PC_IN_CALL_DUMMY) [ON_STACK]: Add comments about stack
+	frame tops and bottoms.
+
+	* frame.h, blockframe.c, stack.c, a29k-tdep.c,
+	config/gould/tmp-{pn,np1}.h,
+	config/{sparc/tm-sparc.h,pyr/tm-pyr.h,vax/tm-vax.h}: Remove field
+	next_frame from struct frame_info.  It has no purpose beyond
+	->next->frame and is an artifact from GDB 2.8.
+
 Tue Jul  6 11:51:18 1993  Jim Kingdon  (kingdon@lioth.cygnus.com)
 
 	* Makefile.in: Remove gdb before creating a new one.
diff --git a/gdb/a29k-tdep.c b/gdb/a29k-tdep.c
index dfb8398..fd90a2b 100644
--- a/gdb/a29k-tdep.c
+++ b/gdb/a29k-tdep.c
@@ -377,7 +377,7 @@ init_frame_info (innermost_frame, fci)
   if (innermost_frame)
     fci->frame = read_register (GR1_REGNUM);
   else
-    fci->frame = fci->next_frame + fci->next->rsize;
+    fci->frame = fci->next->frame + fci->next->rsize;
   
 #if CALL_DUMMY_LOCATION == ON_STACK
   This wont work;
diff --git a/gdb/blockframe.c b/gdb/blockframe.c
index ee42d7c..efcf52b 100644
--- a/gdb/blockframe.c
+++ b/gdb/blockframe.c
@@ -1,6 +1,6 @@
 /* Get info from stack frames;
    convert between frames, blocks, functions and pc values.
-   Copyright (C) 1986, 1987, 1988, 1989 Free Software Foundation, Inc.
+   Copyright 1986, 1987, 1988, 1989, 1991 Free Software Foundation, Inc.
 
 This file is part of GDB.
 
@@ -18,111 +18,75 @@ You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
-#include <stdio.h>
 #include "defs.h"
-#include "param.h"
 #include "symtab.h"
+#include "bfd.h"
+#include "symfile.h"
+#include "objfiles.h"
 #include "frame.h"
 #include "gdbcore.h"
 #include "value.h"		/* for read_register */
 #include "target.h"		/* for target_has_stack */
+#include "inferior.h"		/* for read_pc */
 
-CORE_ADDR read_pc ();		/* In infcmd.c */
-
-/* Start and end of object file containing the entry point.
-   STARTUP_FILE_END is the first address of the next file.
-   This file is assumed to be a startup file
-   and frames with pc's inside it
-   are treated as nonexistent.
-
-   Setting these variables is necessary so that backtraces do not fly off
-   the bottom of the stack.  */
-CORE_ADDR startup_file_start;
-CORE_ADDR startup_file_end;
-
-/* Is ADDR outside the startup file?  Note that if your machine
+/* Is ADDR inside the startup file?  Note that if your machine
    has a way to detect the bottom of the stack, there is no need
    to call this function from FRAME_CHAIN_VALID; the reason for
    doing so is that some machines have no way of detecting bottom
-   of stack.  */
+   of stack. 
+
+   A PC of zero is always considered to be the bottom of the stack. */
+
 int
-outside_startup_file (addr)
+inside_entry_file (addr)
      CORE_ADDR addr;
 {
-  return !(addr >= startup_file_start && addr < startup_file_end);
+  if (addr == 0)
+    return 1;
+  if (symfile_objfile == 0)
+    return 0;
+  return (addr >= symfile_objfile -> ei.entry_file_lowpc &&
+	  addr <  symfile_objfile -> ei.entry_file_highpc);
 }
 
-/* Support an alternate method to avoid running off the bottom of
-   the stack (or top, depending upon your stack orientation).
-
-   There are two frames that are "special", the frame for the function
-   containing the process entry point, since it has no predecessor frame,
-   and the frame for the function containing the user code entry point
-   (the main() function), since all the predecessor frames are for the
-   process startup code.  Since we have no guarantee that the linked
-   in startup modules have any debugging information that gdb can use,
-   we need to avoid following frame pointers back into frames that might
-   have been built in the startup code, as we might get hopelessly 
-   confused.  However, we almost always have debugging information
-   available for main().
-
-   These variables are used to save the range of PC values which are valid
-   within the main() function and within the function containing the process
-   entry point.  If we always consider the frame for main() as the outermost
-   frame when debugging user code, and the frame for the process entry
-   point function as the outermost frame when debugging startup code, then
-   all we have to do is have FRAME_CHAIN_VALID return false whenever a
-   frame's current PC is within the range specified by these variables.
-   In essence, we set "blocks" in the frame chain beyond which we will
-   not proceed when following the frame chain.  
-
-   A nice side effect is that we can still debug startup code without
-   running off the end of the frame chain, assuming that we have usable
-   debugging information in the startup modules, and if we choose to not
-   use the block at main, or can't find it for some reason, everything
-   still works as before.  And if we have no startup code debugging
-   information but we do have usable information for main(), backtraces
-   from user code don't go wandering off into the startup code.
-
-   To use this method, define your FRAME_CHAIN_VALID macro like:
-
-	#define FRAME_CHAIN_VALID(chain, thisframe)     \
-	  (chain != 0                                   \
-	   && !(inside_main_scope ((thisframe)->pc))    \
-	   && !(inside_entry_scope ((thisframe)->pc)))
-
-   and add initializations of the four scope controlling variables inside
-   the object file / debugging information processing modules.  */
-
-CORE_ADDR entry_scope_lowpc;
-CORE_ADDR entry_scope_highpc;
-CORE_ADDR main_scope_lowpc;
-CORE_ADDR main_scope_highpc;
-
 /* Test a specified PC value to see if it is in the range of addresses
    that correspond to the main() function.  See comments above for why
    we might want to do this.
 
-   Typically called from FRAME_CHAIN_VALID. */
+   Typically called from FRAME_CHAIN_VALID.
+
+   A PC of zero is always considered to be the bottom of the stack. */
 
 int
-inside_main_scope (pc)
+inside_main_func (pc)
 CORE_ADDR pc;
 {
-  return (main_scope_lowpc <= pc && pc < main_scope_highpc);
+  if (pc == 0)
+    return 1;
+  if (symfile_objfile == 0)
+    return 0;
+  return (symfile_objfile -> ei.main_func_lowpc  <= pc &&
+	  symfile_objfile -> ei.main_func_highpc > pc);
 }
 
 /* Test a specified PC value to see if it is in the range of addresses
-   that correspond to the process entry point function.  See comments above
-   for why we might want to do this.
+   that correspond to the process entry point function.  See comments
+   in objfiles.h for why we might want to do this.
+
+   Typically called from FRAME_CHAIN_VALID.
 
-   Typically called from FRAME_CHAIN_VALID. */
+   A PC of zero is always considered to be the bottom of the stack. */
 
 int
-inside_entry_scope (pc)
+inside_entry_func (pc)
 CORE_ADDR pc;
 {
-  return (entry_scope_lowpc <= pc && pc < entry_scope_highpc);
+  if (pc == 0)
+    return 1;
+  if (symfile_objfile == 0)
+    return 0;
+  return (symfile_objfile -> ei.entry_func_lowpc  <= pc &&
+	  symfile_objfile -> ei.entry_func_highpc > pc);
 }
 
 /* Address of innermost stack frame (contents of FP register) */
@@ -169,8 +133,8 @@ create_new_frame (addr, pc)
   fci->next = (struct frame_info *) 0;
   fci->prev = (struct frame_info *) 0;
   fci->frame = addr;
-  fci->next_frame = 0;		/* Since arbitrary */
   fci->pc = pc;
+  fci->signal_handler_caller = IN_SIGTRAMP (fci->pc, (char *)NULL);
 
 #ifdef INIT_EXTRA_FRAME_INFO
   INIT_EXTRA_FRAME_INFO (0, fci);
@@ -223,8 +187,7 @@ reinit_frame_cache ()
   FRAME fr = current_frame;
   flush_cached_frames ();
   if (fr)
-    set_current_frame ( create_new_frame (read_register (FP_REGNUM),
-					  read_pc ()));
+    set_current_frame ( create_new_frame (read_fp (), read_pc ()));
 }
 
 /* Return a structure containing various interesting information
@@ -246,7 +209,7 @@ get_frame_info (frame)
    frame_info for the frame, and FRAMELESS should be set to nonzero
    if it represents a frameless function invocation.  */
 
-/* Return nonzero if the function for this frame has a prologue.  Many
+/* Return nonzero if the function for this frame lacks a prologue.  Many
    machines can define FRAMELESS_FUNCTION_INVOCATION to just call this
    function.  */
 
@@ -368,7 +331,47 @@ get_prev_frame_info (next_frame)
   prev->next = next_frame;
   prev->prev = (struct frame_info *) 0;
   prev->frame = address;
-  prev->next_frame = prev->next ? prev->next->frame : 0;
+  prev->signal_handler_caller = 0;
+
+/* This change should not be needed, FIXME!  We should
+   determine whether any targets *need* INIT_FRAME_PC to happen
+   after INIT_EXTRA_FRAME_INFO and come up with a simple way to
+   express what goes on here.
+
+      INIT_EXTRA_FRAME_INFO is called from two places: create_new_frame
+      		(where the PC is already set up) and here (where it isn't).
+      INIT_FRAME_PC is only called from here, always after
+      		INIT_EXTRA_FRAME_INFO.
+   
+   The catch is the MIPS, where INIT_EXTRA_FRAME_INFO requires the PC
+   value (which hasn't been set yet).  Some other machines appear to
+   require INIT_EXTRA_FRAME_INFO before they can do INIT_FRAME_PC.  Phoo.
+
+   We shouldn't need INIT_FRAME_PC_FIRST to add more complication to
+   an already overcomplicated part of GDB.   gnu@cygnus.com, 15Sep92.
+
+   To answer the question, yes the sparc needs INIT_FRAME_PC after
+   INIT_EXTRA_FRAME_INFO.  Suggested scheme:
+
+   SETUP_INNERMOST_FRAME()
+     Default version is just create_new_frame (read_fp ()),
+     read_pc ()).  Machines with extra frame info would do that (or the
+     local equivalent) and then set the extra fields.
+   SETUP_ARBITRARY_FRAME(argc, argv)
+     Only change here is that create_new_frame would no longer init extra
+     frame info; SETUP_ARBITRARY_FRAME would have to do that.
+   INIT_PREV_FRAME(fromleaf, prev)
+     Replace INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC.
+   std_frame_pc(fromleaf, prev)
+     This is the default setting for INIT_PREV_FRAME.  It just does what
+     the default INIT_FRAME_PC does.  Some machines will call it from
+     INIT_PREV_FRAME (either at the beginning, the end, or in the middle).
+     Some machines won't use it.
+   kingdon@cygnus.com, 13Apr93.  */
+
+#ifdef INIT_FRAME_PC_FIRST
+  INIT_FRAME_PC_FIRST (fromleaf, prev);
+#endif
 
 #ifdef INIT_EXTRA_FRAME_INFO
   INIT_EXTRA_FRAME_INFO(fromleaf, prev);
@@ -379,6 +382,9 @@ get_prev_frame_info (next_frame)
      (see tm-sparc.h).  We want the pc saved in the inferior frame. */
   INIT_FRAME_PC(fromleaf, prev);
 
+  if (IN_SIGTRAMP (prev->pc, (char *)NULL))
+    prev->signal_handler_caller = 1;
+
   return prev;
 }
 
@@ -416,7 +422,7 @@ get_frame_block (frame)
   fi = get_frame_info (frame);
 
   pc = fi->pc;
-  if (fi->next_frame != 0)
+  if (fi->next != 0)
     /* We are not in the innermost frame.  We need to subtract one to
        get the correct block, in case the call instruction was the
        last instruction of the block.  If there are any machines on
@@ -436,17 +442,26 @@ CORE_ADDR
 get_pc_function_start (pc)
      CORE_ADDR pc;
 {
-  register struct block *bl = block_for_pc (pc);
+  register struct block *bl;
   register struct symbol *symbol;
-  if (bl == 0 || (symbol = block_function (bl)) == 0)
+  register struct minimal_symbol *msymbol;
+  CORE_ADDR fstart;
+
+  if ((bl = block_for_pc (pc)) != NULL &&
+      (symbol = block_function (bl)) != NULL)
     {
-      register int misc_index = find_pc_misc_function (pc);
-      if (misc_index >= 0)
-	return misc_function_vector[misc_index].address;
-      return 0;
+      bl = SYMBOL_BLOCK_VALUE (symbol);
+      fstart = BLOCK_START (bl);
     }
-  bl = SYMBOL_BLOCK_VALUE (symbol);
-  return BLOCK_START (bl);
+  else if ((msymbol = lookup_minimal_symbol_by_pc (pc)) != NULL)
+    {
+      fstart = SYMBOL_VALUE_ADDRESS (msymbol);
+    }
+  else
+    {
+      fstart = 0;
+    }
+  return (fstart);
 }
 
 /* Return the symbol for the function executing in frame FRAME.  */
@@ -578,7 +593,7 @@ find_pc_partial_function (pc, name, address)
 {
   struct partial_symtab *pst;
   struct symbol *f;
-  int miscfunc;
+  struct minimal_symbol *msymbol;
   struct partial_symbol *psb;
 
   if (pc >= cache_pc_function_low && pc < cache_pc_function_high)
@@ -621,19 +636,18 @@ find_pc_partial_function (pc, name, address)
 	}
 
       /* Get the information from a combination of the pst
-	 (static symbols), and the misc function vector (extern
+	 (static symbols), and the minimal symbol table (extern
 	 symbols).  */
-      miscfunc = find_pc_misc_function (pc);
+      msymbol = lookup_minimal_symbol_by_pc (pc);
       psb = find_pc_psymbol (pst, pc);
 
-      if (!psb && miscfunc == -1)
+      if (!psb && (msymbol == NULL))
 	{
 	  goto return_error;
 	}
       if (psb
-	  && (miscfunc == -1
-	      || (SYMBOL_VALUE_ADDRESS (psb)
-		  >= misc_function_vector[miscfunc].address)))
+	  && (msymbol == NULL ||
+	      (SYMBOL_VALUE_ADDRESS (psb) >= SYMBOL_VALUE_ADDRESS (msymbol))))
 	{
 	  /* This case isn't being cached currently. */
 	  if (address)
@@ -644,23 +658,25 @@ find_pc_partial_function (pc, name, address)
 	}
     }
   else
-    /* Must be in the misc function stuff.  */
+    /* Must be in the minimal symbol table.  */
     {
-      miscfunc = find_pc_misc_function (pc);
-      if (miscfunc == -1)
+      msymbol = lookup_minimal_symbol_by_pc (pc);
+      if (msymbol == NULL)
 	goto return_error;
     }
 
   {
-    if (misc_function_vector[miscfunc].type == mf_text)
-      cache_pc_function_low = misc_function_vector[miscfunc].address;
+    if (msymbol -> type == mst_text)
+      cache_pc_function_low = SYMBOL_VALUE_ADDRESS (msymbol);
     else
       /* It is a transfer table for Sun shared libraries.  */
       cache_pc_function_low = pc - FUNCTION_START_OFFSET;
   }
-  cache_pc_function_name = misc_function_vector[miscfunc].name;
-  if (miscfunc < misc_function_count /* && FIXME mf_text again? */ )
-    cache_pc_function_high = misc_function_vector[miscfunc+1].address;
+  cache_pc_function_name = SYMBOL_NAME (msymbol);
+  /* FIXME:  Deal with bumping into end of minimal symbols for a given
+     objfile, and what about testing for mst_text again? */
+  if (SYMBOL_NAME (msymbol + 1) != NULL)
+    cache_pc_function_high = SYMBOL_VALUE_ADDRESS (msymbol + 1);
   else
     cache_pc_function_high = cache_pc_function_low + 1;
   if (address)
@@ -670,53 +686,11 @@ find_pc_partial_function (pc, name, address)
   return 1;
 }
 
-/* Find the misc function whose address is the largest
-   while being less than PC.  Return its index in misc_function_vector.
-   Returns -1 if PC is not in suitable range.  */
-
-int
-find_pc_misc_function (pc)
-     register CORE_ADDR pc;
-{
-  register int lo = 0;
-  register int hi = misc_function_count-1;
-  register int new;
-
-  /* Note that the last thing in the vector is always _etext.  */
-  /* Actually, "end", now that non-functions
-     go on the misc_function_vector.  */
-
-  /* Above statement is not *always* true - fix for case where there are */
-  /* no misc functions at all (ie no symbol table has been read). */
-  if (hi < 0) return -1;        /* no misc functions recorded */
-
-  /* trivial reject range test */
-  if (pc < misc_function_vector[0].address ||
-      pc > misc_function_vector[hi].address)
-    return -1;
-
-  /* Note that the following search will not return hi if
-     pc == misc_function_vector[hi].address.  If "end" points to the
-     first unused location, this is correct and the above test
-     simply needs to be changed to
-     "pc >= misc_function_vector[hi].address".  */
-  do {
-    new = (lo + hi) >> 1;
-    if (misc_function_vector[new].address == pc)
-      return new;		/* an exact match */
-    else if (misc_function_vector[new].address > pc)
-      hi = new;
-    else
-      lo = new;
-  } while (hi-lo != 1);
-
-  /* if here, we had no exact match, so return the lower choice */
-  return lo;
-}
-
 /* Return the innermost stack frame executing inside of the specified block,
    or zero if there is no such frame.  */
 
+#if 0	/* Currently unused */
+
 FRAME
 block_innermost_frame (block)
      struct block *block;
@@ -738,6 +712,8 @@ block_innermost_frame (block)
     }
 }
 
+#endif	/* 0 */
+
 void
 _initialize_blockframe ()
 {
diff --git a/gdb/config/rs6000/tm-rs6000.h b/gdb/config/rs6000/tm-rs6000.h
index 81ed15c..6350254 100644
--- a/gdb/config/rs6000/tm-rs6000.h
+++ b/gdb/config/rs6000/tm-rs6000.h
@@ -18,21 +18,10 @@ You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 
-extern int	symtab_relocated;
-
 /* Minimum possible text address in AIX */
 
 #define TEXT_SEGMENT_BASE	0x10000000
 
-
-/* text addresses in a core file does not necessarily match to symbol table,
-   if symbol table relocation wasn't done yet. */
-
-#define	CORE_NEEDS_RELOCATION(PC)	\
-  if (!symtab_relocated && !inferior_pid)	\
-    xcoff_relocate_core ();
-extern void xcoff_relocate_core PARAMS ((void));
-
 /* Load segment of a given pc value. */
 
 #define	PC_LOAD_SEGMENT(PC)	pc_load_segment_name(PC)
@@ -42,20 +31,16 @@ extern void xcoff_relocate_core PARAMS ((void));
 #define BELIEVE_PCC_PROMOTION 1
 
 /* return true if a given `pc' value is in `call dummy' function. */
-
+/* FIXME: This just checks for the end of the stack, which is broken
+   for things like stepping through gcc nested function stubs.  */
 #define	PC_IN_CALL_DUMMY(STOP_PC, STOP_SP, STOP_FRAME_ADDR)	\
 	(STOP_SP < STOP_PC && STOP_PC < STACK_END_ADDR)
 
-/* For each symtab, we keep track of which BFD it came from.  */
-#define	EXTRA_SYMTAB_INFO	\
-	unsigned    nonreloc:1;		/* TRUE if non relocatable */
-
-#define	INIT_EXTRA_SYMTAB_INFO(symtab)	\
-	symtab->nonreloc = 0;		\
-
+#if 0
 extern unsigned int text_start, data_start;
-extern int inferior_pid;
 extern char *corefile;
+#endif
+extern int inferior_pid;
 
 /* setpgrp() messes up controling terminal. The other version of it
    requires libbsd.a. */
@@ -114,17 +99,12 @@ function_frame_info PARAMS ((CORE_ADDR, struct aix_framedata *));
 
 /* When a child process is just starting, we sneak in and relocate
    the symbol table (and other stuff) after the dynamic linker has
-   figured out where they go. But we want to do this relocation just
-   once. */
-
-extern int loadinfotextindex;
+   figured out where they go.  */
 
 #define	SOLIB_CREATE_INFERIOR_HOOK(PID)	\
   do {					\
-    if (loadinfotextindex == 0)	\
-	xcoff_relocate_symtab (PID);	\
+    xcoff_relocate_symtab (PID);	\
   } while (0)
-	
 
 /* Number of trap signals we need to skip over, once the inferior process
    starts running. */
@@ -155,15 +135,17 @@ extern int loadinfotextindex;
 
 #define	PROCESS_LINENUMBER_HOOK()	aix_process_linenos ()
    
-   
 /* When a target process or core-file has been attached, we sneak in
-   and figure out where the shared libraries have got to. In case there
-   is no inferior_process exists (e.g. bringing up a core file), we can't
-   attemtp to relocate symbol table, since we don't have information about
-   load segments. */
+   and figure out where the shared libraries have got to.  */
 
 #define	SOLIB_ADD(a, b, c)	\
-   if (inferior_pid)	xcoff_relocate_symtab (inferior_pid)
+  if (inferior_pid)	\
+    /* Attach to process.  */  \
+    xcoff_relocate_symtab (inferior_pid); \
+  else		\
+    /* Core file.  */ \
+    xcoff_relocate_core ();
+extern void xcoff_relocate_core PARAMS ((void));
 
 /* Immediately after a function call, return the saved pc.
    Can't go through the frames for this because on some machines
@@ -401,10 +383,11 @@ extern unsigned int rs6000_struct_return_address;
 /* In the case of the RS6000, the frame's nominal address
    is the address of a 4-byte word containing the calling frame's address.  */
 
-#define FRAME_CHAIN(thisframe)  \
-  (!inside_entry_file ((thisframe)->pc) ?	\
-   read_memory_integer ((thisframe)->frame, 4) :\
-   0)
+#define FRAME_CHAIN(thisframe) rs6000_frame_chain (thisframe)
+#ifdef __STDC__
+struct frame_info;
+#endif
+CORE_ADDR rs6000_frame_chain PARAMS ((struct frame_info *));
 
 /* Define other aspects of the stack frame.  */
 
@@ -426,19 +409,30 @@ extern unsigned int rs6000_struct_return_address;
 	CORE_ADDR initial_sp;			/* initial stack pointer. */ \
 	struct frame_saved_regs *cache_fsr;	/* saved registers	  */
 
+#define INIT_FRAME_PC_FIRST(fromleaf, prev) \
+  prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (prev->next) : \
+	      prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ());
+#define INIT_FRAME_PC(fromleaf, prev) /* nothing */
+#define	INIT_EXTRA_FRAME_INFO(fromleaf, fi)	\
+  fi->initial_sp = 0;		\
+  fi->cache_fsr = 0; \
+  if (fi->next != (CORE_ADDR)0 \
+      && read_memory_integer (fi->frame, 4) == 0 \
+      && fi->pc < TEXT_SEGMENT_BASE) \
+    /* We're in get_prev_frame_info */ \
+    /* and this is a special signal frame.  */ \
+    /* (fi->pc will be something like 0x3f88 or 0x2790).  */ \
+    fi->signal_handler_caller = 1;
+
 /* Frameless function invocation in IBM RS/6000 is sometimes
    half-done. It perfectly sets up a new frame, e.g. a new frame (in
    fact stack) pointer, etc, but it doesn't save the %pc.  We call
    frameless_function_invocation to tell us how to get the %pc.  */
 
-#define	INIT_EXTRA_FRAME_INFO(fromleaf, fi)	\
-	fi->initial_sp = 0;		\
-	fi->cache_fsr = 0;
-
 #define FRAME_SAVED_PC(FRAME)					\
 	(frameless_function_invocation (FRAME, 1)		\
 	 ? SAVED_PC_AFTER_CALL (FRAME)				\
-	 : read_memory_integer (read_memory_integer ((FRAME)->frame, 4)+8, 4))
+	 : read_memory_integer (rs6000_frame_chain (FRAME)+8, 4))
 
 #define FRAME_ARGS_ADDRESS(FI)	\
   (((struct frame_info*)(FI))->initial_sp ?		\
diff --git a/gdb/config/sparc/tm-sparc.h b/gdb/config/sparc/tm-sparc.h
index d4acb9a..a6e5e38 100644
--- a/gdb/config/sparc/tm-sparc.h
+++ b/gdb/config/sparc/tm-sparc.h
@@ -310,13 +310,18 @@ sparc_extract_struct_value_address PARAMS ((char [REGISTER_BYTES]));
    If there is a frame below this one, and the frame pointers are
    identical, it's a leaf frame and the bottoms are the same also.
 
-   Otherwise the bottom of this frame is the top of the next frame.  */
+   Otherwise the bottom of this frame is the top of the next frame.
+
+   The bottom field is misnamed, since it might imply that memory from
+   bottom to frame contains this frame.  That need not be true if
+   stack frames are allocated in different segments (e.g. some on a
+   stack, some on a heap in the data segment).  */
 
 #define EXTRA_FRAME_INFO	FRAME_ADDR bottom;
 #define INIT_EXTRA_FRAME_INFO(fromleaf, fci)  \
   (fci)->bottom =					\
    ((fci)->next ?					\
-    ((fci)->frame == (fci)->next_frame ?		\
+    ((fci)->frame == (fci)->next->frame ?		\
      (fci)->next->bottom : (fci)->next->frame) :	\
     read_register (SP_REGNUM));
 
diff --git a/gdb/config/vax/tm-vax.h b/gdb/config/vax/tm-vax.h
index 8631e04..6fd2454 100644
--- a/gdb/config/vax/tm-vax.h
+++ b/gdb/config/vax/tm-vax.h
@@ -245,16 +245,16 @@ fix to bug-gdb@prep.ai.mit.edu.  */
    So return 0 (indicating we don't know the address of
    the arglist) if we don't know what frame this frame calls.  */
 #define FRAME_ARGS_ADDRESS_CORRECT(fi) \
- (((fi)->next_frame                                  \
-   ? read_memory_integer ((fi)->next_frame + 8, 4)   \
+ (((fi)->next                                  \
+   ? read_memory_integer ((fi)->next->frame + 8, 4)   \
    : /* read_register (AP_REGNUM) */ 0))
 
 /* In most of GDB, getting the args address is too important to
    just say "I don't know".  This is sometimes wrong for functions
    that aren't on top of the stack, but c'est la vie.  */
 #define FRAME_ARGS_ADDRESS(fi) \
- (((fi)->next_frame                                  \
-   ? read_memory_integer ((fi)->next_frame + 8, 4)   \
+ (((fi)->next                                  \
+   ? read_memory_integer ((fi)->next->frame + 8, 4)   \
    : read_register (AP_REGNUM) /* 0 */))
 
 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
diff --git a/gdb/inferior.h b/gdb/inferior.h
index 576fcff..ee1fe09 100644
--- a/gdb/inferior.h
+++ b/gdb/inferior.h
@@ -21,9 +21,6 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 #if !defined (INFERIOR_H)
 #define INFERIOR_H 1
 
-/* For symtab_and_line */
-#include "symtab.h"
-
 /* For bpstat.  */
 #include "breakpoint.h"
 
@@ -110,6 +107,18 @@ read_pc PARAMS ((void));
 extern void
 write_pc PARAMS ((CORE_ADDR));
 
+extern CORE_ADDR
+read_sp PARAMS ((void));
+
+extern void
+write_sp PARAMS ((CORE_ADDR));
+
+extern CORE_ADDR
+read_fp PARAMS ((void));
+
+extern void
+write_fp PARAMS ((CORE_ADDR));
+
 extern void
 wait_for_inferior PARAMS ((void));
 
@@ -188,6 +197,8 @@ fork_inferior PARAMS ((char *, char *, char **,
 extern void
 new_tty_prefork PARAMS ((char *));
 
+extern int gdb_has_a_terminal PARAMS ((void));
+
 /* From infrun.c */
 
 extern void
@@ -300,6 +311,29 @@ extern int pc_changed;
 
 extern int attach_flag;
 
+/* Sigtramp is a routine that the kernel calls (which then calls the
+   signal handler).  On most machines it is a library routine that
+   is linked into the executable.
+
+   This macro, given a program counter value and the name of the
+   function in which that PC resides (which can be null if the
+   name is not known), returns nonzero if the PC and name show
+   that we are in sigtramp.
+
+   On most machines just see if the name is sigtramp (and if we have
+   no name, assume we are not in sigtramp).  */
+#if !defined (IN_SIGTRAMP)
+#  if defined (SIGTRAMP_START)
+#    define IN_SIGTRAMP(pc, name) \
+       ((pc) >= SIGTRAMP_START   \
+        && (pc) < SIGTRAMP_END \
+        )
+#  else
+#    define IN_SIGTRAMP(pc, name) \
+       (name && STREQ ("_sigtramp", name))
+#  endif
+#endif
+
 /* Possible values for CALL_DUMMY_LOCATION.  */
 #define ON_STACK 1
 #define BEFORE_TEXT_END 2
@@ -326,15 +360,23 @@ extern CORE_ADDR text_end;
    && (pc) <= text_end + CALL_DUMMY_LENGTH + DECR_PC_AFTER_BREAK)
 #else /* On stack.  */
 
-/* This assumes that frame_address is the value of SP_REGNUM before
-   the dummy frame was pushed.  The only known machine for which this
-   isn't true is the 29k, which doesn't use ON_STACK.  Machines for
-   which it isn't true who want to put stack dummies on the stack
-   could provide their own PC_IN_CALL_DUMMY, or perhaps this macro
-   could be re-written to check for the end of the stack instead
-   (using the target_ops->sections).  Are there user programs, libraries,
-   kernel routines, etc. which also execute on the stack?  If so, the
-   latter would be a bad idea.  */
+/* Is the PC in a call dummy?  SP and FRAME_ADDRESS are the bottom and
+   top of the stack frame which we are checking, where "bottom" and
+   "top" refer to some section of memory which contains the code for
+   the call dummy.  Calls to this macro assume that the contents of
+   SP_REGNUM and FP_REGNUM (or the saved values thereof), respectively,
+   are the things to pass.
+
+   This won't work on the 29k, where SP_REGNUM and FP_REGNUM don't
+   have that meaning, but the 29k doesn't use ON_STACK.  This could be
+   fixed by generalizing this scheme, perhaps by passing in a frame
+   and adding a few fields, at least on machines which need them for
+   PC_IN_CALL_DUMMY.
+
+   Something simpler, like checking for the stack segment, doesn't work,
+   since various programs (threads implementations, gcc nested function
+   stubs, etc) may either allocate stack frames in another segment, or
+   allocate other kinds of code on the stack.  */
 
 #define PC_IN_CALL_DUMMY(pc, sp, frame_address) \
   ((sp) INNER_THAN (pc) && (frame_address != 0) && (pc) INNER_THAN (frame_address))
diff --git a/gdb/stack.c b/gdb/stack.c
index 0e00586..a0c2d36 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -162,7 +162,7 @@ print_frame_info (fi, level, source, args)
   enum language funlang = language_unknown;
   int numargs;
 
-  if (PC_IN_CALL_DUMMY (fi->pc, read_register (SP_REGNUM), fi->frame))
+  if (PC_IN_CALL_DUMMY (fi->pc, read_sp (), fi->frame))
     {
       /* Do this regardless of SOURCE because we don't have any source
 	 to list for this frame.  */
@@ -181,7 +181,7 @@ print_frame_info (fi, level, source, args)
       return;
     }
 
-  sal = find_pc_line (fi->pc, fi->next_frame);
+  sal = find_pc_line (fi->pc, fi->next);
   func = find_pc_function (fi->pc);
   if (func)
     {
@@ -245,7 +245,7 @@ print_frame_info (fi, level, source, args)
 	  struct print_args_args args;
 	  args.fi = fi;
 	  args.func = func;
-	  catch_errors (print_args_stub, (char *)&args, "");
+	  catch_errors (print_args_stub, (char *)&args, "", RETURN_MASK_ERROR);
 	}
       printf_filtered (")");
       if (sal.symtab && sal.symtab->filename)
@@ -417,7 +417,7 @@ frame_info (addr_exp, from_tty)
     error ("Invalid frame specified.");
 
   fi = get_frame_info (frame);
-  sal = find_pc_line (fi->pc, fi->next_frame);
+  sal = find_pc_line (fi->pc, fi->next);
   func = get_frame_function (frame);
   s = find_pc_symtab(fi->pc);
   if (func)
@@ -475,12 +475,13 @@ frame_info (addr_exp, from_tty)
   if (calling_frame)
     printf_filtered (" called by frame at %s", 
 		     local_hex_string(FRAME_FP (calling_frame)));
-  if (fi->next_frame && calling_frame)
+  if (fi->next && calling_frame)
     puts_filtered (",");
   wrap_here ("   ");
-  if (fi->next_frame)
-    printf_filtered (" caller of frame at %s", local_hex_string(fi->next_frame));
-  if (fi->next_frame || calling_frame)
+  if (fi->next)
+    printf_filtered (" caller of frame at %s",
+		     local_hex_string (fi->next->frame));
+  if (fi->next || calling_frame)
     puts_filtered ("\n");
   if (s)
      printf_filtered(" source language %s.\n", language_str(s->language));