Add -with-frame-pointers to ./configurewith-frame-pointers

git-svn-id: http://caml.inria.fr/svn/ocaml/branches/with-frame-pointers@13729 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

17 files changed, 142 insertions, 42 deletions

diff --git a/.depend b/.depend
index cc07e38700..115bb0cb94 100644
--- a/.depend
+++ b/.depend
@@ -270,18 +270,20 @@ typing/typeclass.cmo : utils/warnings.cmi typing/typetexp.cmi \
     typing/types.cmi typing/typedtree.cmi typing/typedecl.cmi \
     typing/typecore.cmi typing/subst.cmi typing/stypes.cmi \
     typing/printtyp.cmi typing/predef.cmi typing/path.cmi \
-    parsing/parsetree.cmi typing/parmatch.cmi parsing/longident.cmi \
-    parsing/location.cmi typing/includeclass.cmi typing/ident.cmi \
-    typing/env.cmi typing/ctype.cmi typing/cmt_format.cmi utils/clflags.cmi \
-    typing/btype.cmi parsing/asttypes.cmi typing/typeclass.cmi
+    parsing/parsetree.cmi typing/parmatch.cmi utils/misc.cmi \
+    parsing/longident.cmi parsing/location.cmi typing/includeclass.cmi \
+    typing/ident.cmi typing/env.cmi typing/ctype.cmi typing/cmt_format.cmi \
+    utils/clflags.cmi typing/btype.cmi parsing/asttypes.cmi \
+    typing/typeclass.cmi
 typing/typeclass.cmx : utils/warnings.cmx typing/typetexp.cmx \
     typing/types.cmx typing/typedtree.cmx typing/typedecl.cmx \
     typing/typecore.cmx typing/subst.cmx typing/stypes.cmx \
     typing/printtyp.cmx typing/predef.cmx typing/path.cmx \
-    parsing/parsetree.cmi typing/parmatch.cmx parsing/longident.cmx \
-    parsing/location.cmx typing/includeclass.cmx typing/ident.cmx \
-    typing/env.cmx typing/ctype.cmx typing/cmt_format.cmx utils/clflags.cmx \
-    typing/btype.cmx parsing/asttypes.cmi typing/typeclass.cmi
+    parsing/parsetree.cmi typing/parmatch.cmx utils/misc.cmx \
+    parsing/longident.cmx parsing/location.cmx typing/includeclass.cmx \
+    typing/ident.cmx typing/env.cmx typing/ctype.cmx typing/cmt_format.cmx \
+    utils/clflags.cmx typing/btype.cmx parsing/asttypes.cmi \
+    typing/typeclass.cmi
 typing/typecore.cmo : utils/warnings.cmi typing/typetexp.cmi \
     typing/types.cmi typing/typedtree.cmi typing/subst.cmi typing/stypes.cmi \
     typing/printtyp.cmi typing/primitive.cmi typing/predef.cmi \
@@ -382,7 +384,8 @@ bytecomp/printlambda.cmi : bytecomp/lambda.cmi
 bytecomp/runtimedef.cmi :
 bytecomp/simplif.cmi : bytecomp/lambda.cmi
 bytecomp/switch.cmi :
-bytecomp/symtable.cmi : typing/ident.cmi bytecomp/cmo_format.cmi
+bytecomp/symtable.cmi : utils/misc.cmi typing/ident.cmi \
+    bytecomp/cmo_format.cmi
 bytecomp/translclass.cmi : typing/typedtree.cmi parsing/location.cmi \
     bytecomp/lambda.cmi typing/ident.cmi parsing/asttypes.cmi
 bytecomp/translcore.cmi : typing/typedtree.cmi typing/primitive.cmi \
diff --git a/Makefile b/Makefile
index 8f6c913e6d..f0ff364fb2 100644
--- a/Makefile
+++ b/Makefile
@@ -420,6 +420,7 @@ utils/config.ml: utils/config.mlp config/Makefile
 	    -e 's|%%SYSTHREAD_SUPPORT%%|$(SYSTHREAD_SUPPORT)|' \
 	    -e 's|%%ASM%%|$(ASM)|' \
 	    -e 's|%%ASM_CFI_SUPPORTED%%|$(ASM_CFI_SUPPORTED)|' \
+	    -e 's|%%WITH_FRAME_POINTERS%%|$(WITH_FRAME_POINTERS)|' \
 	    -e 's|%%MKDLL%%|$(MKDLL)|' \
 	    -e 's|%%MKEXE%%|$(MKEXE)|' \
 	    -e 's|%%MKMAINDLL%%|$(MKMAINDLL)|' \
diff --git a/Makefile.nt b/Makefile.nt
index 4b25461a90..6c8141355f 100644
--- a/Makefile.nt
+++ b/Makefile.nt
@@ -357,6 +357,7 @@ utils/config.ml: utils/config.mlp config/Makefile
 	    -e "s|%%SYSTHREAD_SUPPORT%%|true|" \
 	    -e 's|%%ASM%%|$(ASM)|' \
 	    -e 's|%%ASM_CFI_SUPPORTED%%|false|' \
+	    -e 's|%%WITH_FRAME_POINTERS%%|false|' \
 	    -e 's|%%MKDLL%%|$(MKDLL)|' \
 	    -e 's|%%MKEXE%%|$(MKEXE)|' \
 	    -e 's|%%MKMAINDLL%%|$(MKMAINDLL)|' \
diff --git a/asmcomp/amd64/emit.mlp b/asmcomp/amd64/emit.mlp
index 447f63d6e3..2b598dbea9 100644
--- a/asmcomp/amd64/emit.mlp
+++ b/asmcomp/amd64/emit.mlp
@@ -23,6 +23,8 @@ open Emitaux
 let macosx = (Config.system = "macosx")
 let mingw64 = (Config.system = "mingw64")
 
+let fp() = Config.with_frame_pointers
+
 (* Tradeoff between code size and code speed *)
 
 let fastcode_flag = ref true
@@ -32,12 +34,13 @@ let stack_offset = ref 0
 (* Layout of the stack frame *)
 
 let frame_required () =
-  !contains_calls || num_stack_slots.(0) > 0 || num_stack_slots.(1) > 0
+  fp() || !contains_calls || num_stack_slots.(0) > 0 || num_stack_slots.(1) > 0
 
 let frame_size () =                     (* includes return address *)
   if frame_required() then begin
     let sz =
-      (!stack_offset + 8 * (num_stack_slots.(0) + num_stack_slots.(1)) + 8)
+      (!stack_offset + 8 * (num_stack_slots.(0) + num_stack_slots.(1)) + 8
+      + (if fp() then 8 else 0) )
     in Misc.align sz 16
   end else
     !stack_offset + 8
@@ -107,13 +110,13 @@ let emit_reg = function
 
 let reg_low_8_name =
   [| "%al"; "%bl"; "%dil"; "%sil"; "%dl"; "%cl"; "%r8b"; "%r9b";
-     "%r12b"; "%r13b"; "%bpl"; "%r10b"; "%r11b" |]
+     "%r12b"; "%r13b"; "%r10b"; "%r11b"; "%bpl" |]
 let reg_low_16_name =
   [| "%ax"; "%bx"; "%di"; "%si"; "%dx"; "%cx"; "%r8w"; "%r9w";
-     "%r12w"; "%r13w"; "%bp"; "%r10w"; "%r11w" |]
+     "%r12w"; "%r13w"; "%r10w"; "%r11w"; "%bp" |]
 let reg_low_32_name =
   [| "%eax"; "%ebx"; "%edi"; "%esi"; "%edx"; "%ecx"; "%r8d"; "%r9d";
-     "%r12d"; "%r13d"; "%ebp"; "%r10d"; "%r11d" |]
+     "%r12d"; "%r13d"; "%r10d"; "%r11d"; "%ebp" |]
 
 let emit_subreg tbl r =
   match r.loc with
@@ -316,9 +319,12 @@ let emit_float_test cmp neg arg lbl =
 
 let output_epilogue f =
   if frame_required() then begin
-    let n = frame_size() - 8 in
+    let n = frame_size() - 8 - (if fp() then 8 else 0) in
     `	addq	${emit_int n}, %rsp\n`;
     cfi_adjust_cfa_offset (-n);
+    if fp() then begin
+       `	popq	%rbp\n`
+    end;
     f ();
     (* reset CFA back cause function body may continue *)
     cfi_adjust_cfa_offset n
@@ -696,7 +702,8 @@ let emit_profile () =
          need to preserve other regs.  We do need to initialize rbp
          like mcount expects it, though. *)
       `	pushq	%r10\n`;
-      `	movq	%rsp, %rbp\n`;
+      if not Config.with_frame_pointers then
+        `	movq	%rsp, %rbp\n`;
       `	{emit_call "mcount"}\n`;
       `	popq	%r10\n`
   | _ ->
@@ -724,9 +731,14 @@ let fundecl fundecl =
   `{emit_symbol fundecl.fun_name}:\n`;
   emit_debug_info fundecl.fun_dbg;
   cfi_startproc ();
+  if fp() then begin
+       `	pushq	%rbp\n`;
+       cfi_adjust_cfa_offset 8;
+       `	movq	%rsp, %rbp\n`;
+  end;
   if !Clflags.gprofile then emit_profile();
   if frame_required() then begin
-    let n = frame_size() - 8 in
+    let n = frame_size() - 8 - (if fp() then 8 else 0) in
     `	subq	${emit_int n}, %rsp\n`;
     cfi_adjust_cfa_offset n;
   end;
diff --git a/asmcomp/amd64/proc.ml b/asmcomp/amd64/proc.ml
index 351770b281..3d065bc0bf 100644
--- a/asmcomp/amd64/proc.ml
+++ b/asmcomp/amd64/proc.ml
@@ -45,9 +45,9 @@ let masm =
     r9          7
     r12         8
     r13         9
-    rbp         10
-    r10         11
-    r11         12
+    r10         10
+    r11         11
+    rbp         12
     r14         trap pointer
     r15         allocation pointer
 
@@ -77,10 +77,10 @@ let int_reg_name =
   match Config.ccomp_type with
   | "msvc" ->
       [| "rax"; "rbx"; "rdi"; "rsi"; "rdx"; "rcx"; "r8"; "r9";
-         "r12"; "r13"; "rbp"; "r10"; "r11" |]
+         "r12"; "r13"; "r10"; "r11"; "rbp" |]
   | _ ->
       [| "%rax"; "%rbx"; "%rdi"; "%rsi"; "%rdx"; "%rcx"; "%r8"; "%r9";
-         "%r12"; "%r13"; "%rbp"; "%r10"; "%r11" |]
+         "%r12"; "%r13"; "%r10"; "%r11"; "%rbp" |]
 
 let float_reg_name =
   match Config.ccomp_type with
@@ -133,6 +133,7 @@ let phys_reg n =
 let rax = phys_reg 0
 let rcx = phys_reg 5
 let rdx = phys_reg 4
+let rbp = phys_reg 12
 let rxmm15 = phys_reg 115
 
 let stack_slot slot ty =
@@ -242,12 +243,12 @@ let destroyed_at_c_call =
   if win64 then
     (* Win64: rbx, rbp, rsi, rdi, r12-r15, xmm6-xmm15 preserved *)
     Array.of_list(List.map phys_reg
-      [0;4;5;6;7;11;12;
+      [0;4;5;6;7;10;11;
        100;101;102;103;104;105])
   else
     (* Unix: rbp, rbx, r12-r15 preserved *)
     Array.of_list(List.map phys_reg
-      [0;2;3;4;5;6;7;11;12;
+      [0;2;3;4;5;6;7;10;11;
        100;101;102;103;104;105;106;107;
        108;109;110;111;112;113;114;115])
 
@@ -259,23 +260,37 @@ let destroyed_at_oper = function
   | Iop(Ialloc _ | Iintop(Icomp _) | Iintop_imm((Idiv|Imod|Icomp _), _))
         -> [| rax |]
   | Iswitch(_, _) -> [| rax; rdx |]
-  | _ -> [||]
+  | _ ->
+    if Config.with_frame_pointers then
+(* prevent any use of the frame pointer ! *)
+      [| rbp |]
+    else
+      [||]
+
 
 let destroyed_at_raise = all_phys_regs
 
 (* Maximal register pressure *)
 
+let fp() = Config.with_frame_pointers
+
 let safe_register_pressure = function
-    Iextcall(_,_) -> if win64 then 8 else 0
-  | _ -> 11
+    Iextcall(_,_) -> if win64 then if fp() then 7 else 8 else 0
+  | _ -> if fp() then 10 else 11
 
 let max_register_pressure = function
-    Iextcall(_, _) -> if win64 then [| 8; 10 |] else [| 4; 0 |]
-  | Iintop(Idiv | Imod) -> [| 11; 16 |]
-  | Ialloc _ | Iintop(Icomp _) | Iintop_imm((Idiv|Imod|Icomp _), _)
-        -> [| 12; 16 |]
-  | Istore(Single, _) -> [| 13; 15 |]
-  | _ -> [| 13; 16 |]
+    Iextcall(_, _) ->
+      if win64 then
+        if fp() then [| 7; 10 |]  else [| 8; 10 |]
+        else
+        if fp() then [| 3; 0 |] else  [| 4; 0 |]
+  | Iintop(Idiv | Imod) ->
+    if fp() then [| 10; 16 |] else [| 11; 16 |]
+  | Ialloc _ | Iintop(Icomp _) | Iintop_imm((Idiv|Imod|Icomp _), _) ->
+    if fp() then [| 11; 16 |] else [| 12; 16 |]
+  | Istore(Single, _) ->
+    if fp() then [| 12; 15 |] else [| 13; 15 |]
+  | _ -> if fp() then [| 12; 16 |] else [| 13; 16 |]
 
 (* Layout of the stack frame *)
 
@@ -292,3 +307,9 @@ let assemble_file infile outfile =
   else
     Ccomp.command (Config.asm ^ " -o " ^
                    Filename.quote outfile ^ " " ^ Filename.quote infile)
+
+let init () =
+  if fp () then begin
+    num_available_registers.(0) <- 12
+  end else
+    num_available_registers.(0) <- 13
diff --git a/asmcomp/arm/proc.ml b/asmcomp/arm/proc.ml
index b8ff779b63..dbb13173a9 100644
--- a/asmcomp/arm/proc.ml
+++ b/asmcomp/arm/proc.ml
@@ -233,3 +233,6 @@ let contains_calls = ref false
 let assemble_file infile outfile =
   Ccomp.command (Config.asm ^ " -o " ^
                  Filename.quote outfile ^ " " ^ Filename.quote infile)
+
+
+let init () = ()
diff --git a/asmcomp/asmgen.ml b/asmcomp/asmgen.ml
index 448980740c..40f7dafbd0 100644
--- a/asmcomp/asmgen.ml
+++ b/asmcomp/asmgen.ml
@@ -57,6 +57,7 @@ let rec regalloc ppf round fd =
 let (++) x f = f x
 
 let compile_fundecl (ppf : formatter) fd_cmm =
+  Proc.init ();
   Reg.reset();
   fd_cmm
   ++ Selection.fundecl
diff --git a/asmcomp/emitaux.ml b/asmcomp/emitaux.ml
index c3f8888515..3ad467cbff 100644
--- a/asmcomp/emitaux.ml
+++ b/asmcomp/emitaux.ml
@@ -220,7 +220,8 @@ let reset_debug_info () =
    display .loc for every instruction. *)
 let emit_debug_info dbg =
   if is_cfi_enabled () &&
-    !Clflags.debug && not (Debuginfo.is_none dbg) then begin
+    (!Clflags.debug || Config.with_frame_pointers)
+     && not (Debuginfo.is_none dbg) then begin
     let line = dbg.Debuginfo.dinfo_line in
     assert (line <> 0); (* clang errors out on zero line numbers *)
     let file_name = dbg.Debuginfo.dinfo_file in
diff --git a/asmcomp/i386/proc.ml b/asmcomp/i386/proc.ml
index bb510bbf40..4cecb2d44f 100644
--- a/asmcomp/i386/proc.ml
+++ b/asmcomp/i386/proc.ml
@@ -198,3 +198,6 @@ let assemble_file infile outfile =
   else
     Ccomp.command (Config.asm ^ " -o " ^
                    Filename.quote outfile ^ " " ^ Filename.quote infile)
+
+let init () = ()
+
diff --git a/asmcomp/power/proc.ml b/asmcomp/power/proc.ml
index feb38f2538..38adadc05a 100644
--- a/asmcomp/power/proc.ml
+++ b/asmcomp/power/proc.ml
@@ -237,3 +237,5 @@ let assemble_file infile outfile =
 
 open Clflags;;
 open Config;;
+
+let init () = ()
diff --git a/asmcomp/proc.mli b/asmcomp/proc.mli
index 91a480b097..6cc6aedc90 100644
--- a/asmcomp/proc.mli
+++ b/asmcomp/proc.mli
@@ -46,3 +46,6 @@ val contains_calls: bool ref
 
 (* Calling the assembler *)
 val assemble_file: string -> string -> int
+
+(* Called before translating a fundecl. *)
+val init : unit -> unit
diff --git a/asmcomp/sparc/proc.ml b/asmcomp/sparc/proc.ml
index b88d5aaae4..ed107a82a7 100644
--- a/asmcomp/sparc/proc.ml
+++ b/asmcomp/sparc/proc.ml
@@ -211,3 +211,5 @@ let assemble_file infile outfile =
   end in
   Ccomp.command (Config.asm ^ asflags ^
                  Filename.quote outfile ^ " " ^ Filename.quote infile)
+
+let init () = ()
diff --git a/asmrun/amd64.S b/asmrun/amd64.S
index dd03c75d1b..5924e4311f 100644
--- a/asmrun/amd64.S
+++ b/asmrun/amd64.S
@@ -73,6 +73,19 @@
 #define CFI_ADJUST(n)
 #endif
 
+#ifdef WITH_FRAME_POINTERS
+#define ENTER_FUNCTION \
+        pushq   %rbp; CFI_ADJUST(8); \
+        movq    %rsp, %rbp
+#define LEAVE_FUNCTION \
+        popq    %rbp; CFI_ADJUST(-8);
+#else
+#define ENTER_FUNCTION \
+	subl	$8, %rsp; CFI_ADJUST(8)
+#define LEAVE_FUNCTION \
+	addl	$8, %rsp; CFI_ADJUST(-8)
+#endif
+
 #if defined(__PIC__) && !defined(SYS_mingw64)
 
 /* Position-independent operations on global variables. */
@@ -200,8 +213,8 @@
 /* Unix API: callee-save regs are rbx, rbp, r12-r15 */
 
 #define PUSH_CALLEE_SAVE_REGS \
+	ENTER_FUNCTION; \
         pushq   %rbx; CFI_ADJUST(8); \
-        pushq   %rbp; CFI_ADJUST(8); \
         pushq   %r12; CFI_ADJUST(8); \
         pushq   %r13; CFI_ADJUST(8); \
         pushq   %r14; CFI_ADJUST(8); \
@@ -214,8 +227,8 @@
         popq    %r14; CFI_ADJUST(-8); \
         popq    %r13; CFI_ADJUST(-8); \
         popq    %r12; CFI_ADJUST(-8); \
-        popq    %rbp; CFI_ADJUST(-8); \
-        popq    %rbx; CFI_ADJUST(-8)
+        popq    %rbx; CFI_ADJUST(-8); \
+	LEAVE_FUNCTION
 
 #endif
 
@@ -232,6 +245,8 @@
 
         .globl  G(caml_system__code_begin)
 G(caml_system__code_begin):
+        ret  /* just one instruction, so that debuggers don't display
+        caml_system__code_begin instead of caml_call_gc */
 
 /* Allocation */
 
@@ -247,9 +262,9 @@ LBL(caml_call_gc):
         addq    $32768, %rsp
 #endif
     /* Build array of registers, save it into caml_gc_regs */
+	ENTER_FUNCTION		;
         pushq   %r11; CFI_ADJUST (8);
         pushq   %r10; CFI_ADJUST (8);
-        pushq   %rbp; CFI_ADJUST (8);
         pushq   %r13; CFI_ADJUST (8);
         pushq   %r12; CFI_ADJUST (8);
         pushq   %r9; CFI_ADJUST (8);
@@ -317,9 +332,9 @@ LBL(caml_call_gc):
         popq    %r9; CFI_ADJUST(-8)
         popq    %r12; CFI_ADJUST(-8)
         popq    %r13; CFI_ADJUST(-8)
-        popq    %rbp; CFI_ADJUST(-8)
         popq    %r10; CFI_ADJUST(-8)
         popq    %r11; CFI_ADJUST(-8)
+	LEAVE_FUNCTION		
     /* Return to caller */
         ret
 CFI_ENDPROC
@@ -333,9 +348,11 @@ LBL(caml_alloc1):
         ret
 LBL(100):
         RECORD_STACK_FRAME(0)
+	ENTER_FUNCTION
         subq    $8, %rsp; CFI_ADJUST (8);
         call    LBL(caml_call_gc)
         addq    $8, %rsp; CFI_ADJUST (-8);
+	LEAVE_FUNCTION
         jmp     LBL(caml_alloc1)
 CFI_ENDPROC
 
@@ -348,9 +365,11 @@ LBL(caml_alloc2):
         ret
 LBL(101):
         RECORD_STACK_FRAME(0)
+	ENTER_FUNCTION
         subq    $8, %rsp; CFI_ADJUST (8);
         call    LBL(caml_call_gc)
         addq    $8, %rsp; CFI_ADJUST (-8);
+	LEAVE_FUNCTION
         jmp     LBL(caml_alloc2)
 CFI_ENDPROC
 
@@ -363,9 +382,11 @@ LBL(caml_alloc3):
         ret
 LBL(102):
         RECORD_STACK_FRAME(0)
+	ENTER_FUNCTION
         subq    $8, %rsp; CFI_ADJUST (8)
         call    LBL(caml_call_gc)
         addq    $8, %rsp; CFI_ADJUST (-8)
+	LEAVE_FUNCTION
         jmp     LBL(caml_alloc3)
 CFI_ENDPROC
 
@@ -380,8 +401,10 @@ LBL(caml_allocN):
         ret
 LBL(103):
         RECORD_STACK_FRAME(8)
+	ENTER_FUNCTION
         call    LBL(caml_call_gc)
         popq    %rax; CFI_ADJUST(-8)       /* recover desired size */
+	LEAVE_FUNCTION
         jmp     LBL(caml_allocN)
 CFI_ENDPROC
 
@@ -486,12 +509,14 @@ CFI_STARTPROC
         popq    %r14
         ret
 LBL(110):
+	ENTER_FUNCTION
         movq    %rax, %r12            /* Save exception bucket */
         movq    %rax, C_ARG_1         /* arg 1: exception bucket */
-        popq    C_ARG_2               /* arg 2: pc of raise */
-        movq    %rsp, C_ARG_3         /* arg 3: sp at raise */
+        movq	8(%rsp), C_ARG_2      /* arg 2: pc of raise */
+        leaq    16(%rsp), C_ARG_3     /* arg 3: sp at raise */
         movq    %r14, C_ARG_4         /* arg 4: sp of handler */
         /* PR#5700: thanks to popq above, stack is now 16-aligned */
+	/* Thanks to ENTER_FUNCTION, stack is now 16-aligned */
         PREPARE_FOR_C_CALL            /* no need to cleanup after */
         call    GCALL(caml_stash_backtrace)
         movq    %r12, %rax            /* Recover exception bucket */
@@ -512,6 +537,7 @@ CFI_STARTPROC
         LOAD_VAR(caml_young_ptr, %r15) /* Reload alloc ptr */
         ret
 LBL(111):
+        ENTER_FUNCTION
         movq    C_ARG_1, %r12            /* Save exception bucket */
                                       /* arg 1: exception bucket */
         LOAD_VAR(caml_last_return_address,C_ARG_2)   /* arg 2: pc of raise */
diff --git a/configure b/configure
index e89076d69d..599d855ada 100755
--- a/configure
+++ b/configure
@@ -43,6 +43,7 @@ withsharedlibs=yes
 gcc_warnings="-Wall"
 partialld="ld -r"
 withcamlp4=camlp4
+with_frame_pointers=false
 
 # Try to turn internationalization off, can cause config.guess to malfunction!
 unset LANG
@@ -115,6 +116,8 @@ while : ; do
         debugruntime=runtimed;;
     -no-camlp4|--no-camlp4)
         withcamlp4="";;
+    -with-frame-pointers|--with-frame-pointers)
+        with_frame_pointers=true;;
     *) echo "Unknown option \"$1\"." 1>&2; exit 2;;
   esac
   shift
@@ -1577,6 +1580,13 @@ else
   echo "Assembler does not support CFI"
 fi
 
+if test "$with_frame_pointers" = "true"; then
+  nativecccompopts="$nativecccompopts -g"
+  nativecclinkopts="$nativecclinkopts -g"
+  echo "#define WITH_FRAME_POINTERS" >> m.h
+fi
+
+
 # Final twiddling of compiler options to work around known bugs
 
 nativeccprofopts="$nativecccompopts"
@@ -1650,6 +1660,7 @@ echo "MKMAINDLL=$mkmaindll" >> Makefile
 echo "RUNTIMED=${debugruntime}" >>Makefile
 echo "CAMLP4=${withcamlp4}" >>Makefile
 echo "ASM_CFI_SUPPORTED=$asm_cfi_supported" >> Makefile
+echo "WITH_FRAME_POINTERS=$with_frame_pointers" >> Makefile
 if [ "$ostype" = Cygwin ]; then
   echo "DIFF=diff -q --strip-trailing-cr" >>Makefile
 fi
@@ -1703,6 +1714,11 @@ else
   else
   echo "        assembler supports CFI ... no"
   fi
+  if test "$with_frame_pointers" = "true"; then
+  echo "        with frame pointers....... yes"
+  else
+  echo "        with frame pointers....... no"
+  fi
   echo "        native dynlink ........... $natdynlink"
   if test "$profiling" = "prof"; then
   echo "        profiling with gprof ..... supported"
diff --git a/utils/clflags.ml b/utils/clflags.ml
index dd914cdbb9..bdb9feb713 100644
--- a/utils/clflags.ml
+++ b/utils/clflags.ml
@@ -99,4 +99,5 @@ let std_include_dir () =
 let shared = ref false (* -shared *)
 let dlcode = ref true (* not -nodynlink *)
 
-let runtime_variant = ref "";;     (* -runtime-variant *)
+let runtime_variant = ref "";;      (* -runtime-variant *)
+
diff --git a/utils/config.mli b/utils/config.mli
index 7829b9ee17..d8c02006b9 100644
--- a/utils/config.mli
+++ b/utils/config.mli
@@ -101,6 +101,8 @@ val asm: string
 
 val asm_cfi_supported: bool
         (* Whether assembler understands CFI directives *)
+val with_frame_pointers : bool
+        (* Whether assembler should maintain frame pointers *)
 
 val ext_obj: string
         (* Extension for object files, e.g. [.o] under Unix. *)
diff --git a/utils/config.mlp b/utils/config.mlp
index 4f3a40512a..6f6fe40c8e 100644
--- a/utils/config.mlp
+++ b/utils/config.mlp
@@ -78,6 +78,7 @@ let system = "%%SYSTEM%%"
 
 let asm = "%%ASM%%"
 let asm_cfi_supported = %%ASM_CFI_SUPPORTED%%
+let with_frame_pointers = %%WITH_FRAME_POINTERS%%
 
 let ext_obj = "%%EXT_OBJ%%"
 let ext_asm = "%%EXT_ASM%%"
@@ -112,6 +113,7 @@ let print_config oc =
   p "system" system;
   p "asm" asm;
   p_bool "asm_cfi_supported" asm_cfi_supported;
+  p_bool "with_frame_pointers" with_frame_pointers;
   p "ext_obj" ext_obj;
   p "ext_asm" ext_asm;
   p "ext_lib" ext_lib;