Use fixed configuration for boot/ocamlc

Use the same configuration for boot/ocamlc regardless of the machine on
which the bootstrap is performed. Now set Config.in_boot_compiler to
true for boot/ocamlc.

9 files changed, 285 insertions, 156 deletions

diff --git a/.depend b/.depend
index 6fdf87ceca..79d4c29b02 100644
--- a/.depend
+++ b/.depend
@@ -45,11 +45,25 @@ utils/clflags.cmx : \
 utils/clflags.cmi : \
     utils/profile.cmi \
     utils/misc.cmi
+utils/config.common.cmo :
+utils/config.common.cmx :
+utils/config.fixed.cmo :
+utils/config.fixed.cmx :
 utils/config.cmo : \
     utils/config.cmi
 utils/config.cmx : \
     utils/config.cmi
 utils/config.cmi :
+utils/config_boot.cmo : \
+    utils/config_boot.cmi
+utils/config_boot.cmx : \
+    utils/config_boot.cmi
+utils/config_boot.cmi :
+utils/config_main.cmo : \
+    utils/config_main.cmi
+utils/config_main.cmx : \
+    utils/config_main.cmi
+utils/config_main.cmi :
 utils/consistbl.cmo : \
     utils/misc.cmi \
     utils/consistbl.cmi
diff --git a/.gitignore b/.gitignore
index de7472e741..c34c9daf05 100644
--- a/.gitignore
+++ b/.gitignore
@@ -244,6 +244,7 @@ _build
 /toplevel/native/trace.mli
 /toplevel/native/topmain.mli
 
+/utils/config_*.ml*
 /utils/config.ml
 /utils/domainstate.ml
 /utils/domainstate.mli
diff --git a/Makefile b/Makefile
index 25859059c7..46cb8f739d 100644
--- a/Makefile
+++ b/Makefile
@@ -97,9 +97,18 @@ include compilerlibs/Makefile.compilerlibs
 
 # The configuration file
 
-utils/config.ml: utils/config.mlp Makefile.config utils/Makefile
+CONFIG_MODULE_DEPENDENCIES = \
+  utils/config.common.ml Makefile.config utils/Makefile
+
+utils/config.ml: utils/config_main.ml utils/config_boot.ml
 	$(MAKE) -C utils config.ml
 
+utils/config_main.ml: utils/config.mlp $(CONFIG_MODULE_DEPENDENCIES)
+	$(MAKE) -C utils config_main.ml
+
+utils/config_boot.ml: utils/config.fixed.ml $(CONFIG_MODULE_DEPENDENCIES)
+	$(MAKE) -C utils config_boot.ml
+
 .PHONY: reconfigure
 reconfigure:
 	ac_read_git_config=true ./configure $(CONFIGURE_ARGS)
@@ -115,7 +124,9 @@ configure: configure.ac aclocal.m4 build-aux/ocaml_version.m4 tools/autogen
 
 .PHONY: partialclean
 partialclean::
-	rm -f utils/config.ml utils/domainstate.ml utils/domainstate.mli
+	rm -f utils/config.ml utils/config_main.ml utils/config_main.mli \
+        utils/config_boot.ml utils/config_boot.mli \
+        utils/domainstate.ml utils/domainstate.mli
 
 .PHONY: beforedepend
 beforedepend:: utils/config.ml utils/domainstate.ml utils/domainstate.mli
@@ -268,15 +279,17 @@ coreboot:
 # runtime/ocamlrun
 	$(MAKE) promote-cross
 # Rebuild ocamlc and ocamllex (run on runtime/ocamlrun)
+# utils/config.ml will have the fixed bootstrap configuration
 	$(MAKE) partialclean
-	$(MAKE) ocamlc ocamllex ocamltools
+	$(MAKE) IN_COREBOOT_CYCLE=true ocamlc ocamllex ocamltools
 # Rebuild the library (using runtime/ocamlrun ./ocamlc)
 	$(MAKE) library-cross
 # Promote the new compiler and the new runtime
 	$(MAKE) OCAMLRUN=runtime/ocamlrun$(EXE) promote
 # Rebuild the core system
+# utils/config.ml must still have the fixed bootstrap configuration
 	$(MAKE) partialclean
-	$(MAKE) core
+	$(MAKE) IN_COREBOOT_CYCLE=true core
 # Check if fixpoint reached
 	$(MAKE) compare
 else
@@ -301,6 +314,8 @@ endif
 # Never mind, just do make bootstrap to reach fixpoint again.
 .PHONY: bootstrap
 bootstrap: coreboot
+# utils/config.ml must be restored to config.status's configuration
+	rm -f utils/config.ml
 	$(MAKE) all
 
 # Compile everything the first time
diff --git a/Makefile.common b/Makefile.common
index 61fb3e9f18..89f3e5795c 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -39,6 +39,8 @@ INSTALL_DOCDIR := $(DESTDIR)$(DOCDIR)
 
 FLEXDLL_SUBMODULE_PRESENT := $(wildcard $(ROOTDIR)/flexdll/Makefile)
 
+IN_COREBOOT_CYCLE ?= false
+
 # Variables used to represent the OCaml runtime system
 # Most of the time, boot/ocamlrun and runtime/ocamlrun are the same.
 # However, under some circumstances it is important to be able to
diff --git a/compilerlibs/Makefile.compilerlibs b/compilerlibs/Makefile.compilerlibs
index f6618999fc..4eb49ca60d 100644
--- a/compilerlibs/Makefile.compilerlibs
+++ b/compilerlibs/Makefile.compilerlibs
@@ -406,8 +406,14 @@ partialclean::
 $(COMMON:.cmo=.cmx) $(BYTECOMP:.cmo=.cmx) $(OPTCOMP:.cmo=.cmx): ocamlopt$(EXE)
 $(OPTTOPLEVEL:.cmo=.cmx): ocamlopt$(EXE)
 
+ALL_CONFIG_CMO = utils/config_main.cmo utils/config_boot.cmo
 
-compilerlibs/ocamlcommon.cma: $(COMMON_CMI) $(COMMON)
+utils/config_%.mli: utils/config.mli
+	cp $^ $@
+
+beforedepend:: utils/config_main.mli utils/config_boot.mli
+
+compilerlibs/ocamlcommon.cma: $(COMMON_CMI) $(ALL_CONFIG_CMO) $(COMMON)
 	$(CAMLC) -a -linkall -o $@ $(COMMON)
 partialclean::
 	rm -f compilerlibs/ocamlcommon.cma
diff --git a/utils/Makefile b/utils/Makefile
index 7ccc9cf413..9c26fddba1 100644
--- a/utils/Makefile
+++ b/utils/Makefile
@@ -37,9 +37,7 @@ SUBST_QUOTE=$(call SUBST_QUOTE2,$1,$($1))
 FLEXLINK_LDFLAGS=$(if $(OC_LDFLAGS), -link "$(OC_LDFLAGS)")
 FLEXLINK_DLL_LDFLAGS=$(if $(OC_DLL_LDFLAGS), -link "$(OC_DLL_LDFLAGS)")
 
-IN_COREBOOT_CYCLE?=false
-
-config.ml: config.mlp $(ROOTDIR)/Makefile.config Makefile
+config_main.ml: config.mlp $(ROOTDIR)/Makefile.config Makefile config.common.ml
 	sed $(call SUBST,AFL_INSTRUMENT) \
 	    $(call SUBST,ARCH) \
 	    $(call SUBST_STRING,ARCMD) \
@@ -89,8 +87,14 @@ config.ml: config.mlp $(ROOTDIR)/Makefile.config Makefile
 	    $(call SUBST,CC_HAS_DEBUG_PREFIX_MAP) \
 	    $(call SUBST,AS_HAS_DEBUG_PREFIX_MAP) \
 	    $(call SUBST,FORCE_INSTRUMENTED_RUNTIME) \
-	    $(call SUBST,IN_COREBOOT_CYCLE) \
 	    $< > $@
+	cat config.common.ml >> $@
+
+config_boot.ml: config.fixed.ml config.common.ml Makefile
+	cat config.fixed.ml config.common.ml > $@
+
+config.ml: config_$(if $(filter true,$(IN_COREBOOT_CYCLE)),boot,main).ml
+	cp $^ $@
 
 # Test for the substitution functions above
 
diff --git a/utils/config.common.ml b/utils/config.common.ml
new file mode 100644
index 0000000000..13eb6392b8
--- /dev/null
+++ b/utils/config.common.ml
@@ -0,0 +1,162 @@
+#2 "utils/config.common.ml"
+(**************************************************************************)
+(*                                                                        *)
+(*                                 OCaml                                  *)
+(*                                                                        *)
+(*             Xavier Leroy, projet Cristal, INRIA Rocquencourt           *)
+(*                                                                        *)
+(*   Copyright 1996 Institut National de Recherche en Informatique et     *)
+(*     en Automatique.                                                    *)
+(*                                                                        *)
+(*   All rights reserved.  This file is distributed under the terms of    *)
+(*   the GNU Lesser General Public License version 2.1, with the          *)
+(*   special exception on linking described in the file LICENSE.          *)
+(*                                                                        *)
+(**************************************************************************)
+
+(* Portions of the Config module common to both the boot and main compiler. *)
+
+(* The main OCaml version string has moved to ../build-aux/ocaml_version.m4 *)
+let version = Sys.ocaml_version
+
+let standard_library =
+  try
+    Sys.getenv "OCAMLLIB"
+  with Not_found ->
+  try
+    Sys.getenv "CAMLLIB"
+  with Not_found ->
+    standard_library_default
+
+let exec_magic_number = "Caml1999X031"
+    (* exec_magic_number is duplicated in runtime/caml/exec.h *)
+and cmi_magic_number = "Caml1999I031"
+and cmo_magic_number = "Caml1999O031"
+and cma_magic_number = "Caml1999A031"
+and cmx_magic_number =
+  if flambda then
+    "Caml1999y031"
+  else
+    "Caml1999Y031"
+and cmxa_magic_number =
+  if flambda then
+    "Caml1999z031"
+  else
+    "Caml1999Z031"
+and ast_impl_magic_number = "Caml1999M031"
+and ast_intf_magic_number = "Caml1999N031"
+and cmxs_magic_number = "Caml1999D031"
+and cmt_magic_number = "Caml1999T031"
+and linear_magic_number = "Caml1999L031"
+
+let safe_string = true
+let default_safe_string = true
+let naked_pointers = false
+
+let interface_suffix = ref ".mli"
+
+let max_tag = 243
+(* This is normally the same as in obj.ml, but we have to define it
+   separately because it can differ when we're in the middle of a
+   bootstrapping phase. *)
+let lazy_tag = 246
+
+let max_young_wosize = 256
+let stack_threshold = 32 (* see runtime/caml/config.h *)
+let stack_safety_margin = 6
+let default_executable_name =
+  match Sys.os_type with
+    "Unix" -> "a.out"
+  | "Win32" | "Cygwin" -> "camlprog.exe"
+  | _ -> "camlprog"
+type configuration_value =
+  | String of string
+  | Int of int
+  | Bool of bool
+
+let configuration_variables =
+  let p x v = (x, String v) in
+  let p_int x v = (x, Int v) in
+  let p_bool x v = (x, Bool v) in
+[
+  p "version" version;
+  p "standard_library_default" standard_library_default;
+  p "standard_library" standard_library;
+  p "ccomp_type" ccomp_type;
+  p "c_compiler" c_compiler;
+  p "ocamlc_cflags" ocamlc_cflags;
+  p "ocamlc_cppflags" ocamlc_cppflags;
+  p "ocamlopt_cflags" ocamlopt_cflags;
+  p "ocamlopt_cppflags" ocamlopt_cppflags;
+  p "bytecomp_c_compiler" bytecomp_c_compiler;
+  p "native_c_compiler" native_c_compiler;
+  p "bytecomp_c_libraries" bytecomp_c_libraries;
+  p "native_c_libraries" native_c_libraries;
+  p "native_pack_linker" native_pack_linker;
+  p "architecture" architecture;
+  p "model" model;
+  p_int "int_size" Sys.int_size;
+  p_int "word_size" Sys.word_size;
+  p "system" system;
+  p "asm" asm;
+  p_bool "asm_cfi_supported" asm_cfi_supported;
+  p_bool "with_frame_pointers" with_frame_pointers;
+  p "ext_exe" ext_exe;
+  p "ext_obj" ext_obj;
+  p "ext_asm" ext_asm;
+  p "ext_lib" ext_lib;
+  p "ext_dll" ext_dll;
+  p "os_type" Sys.os_type;
+  p "default_executable_name" default_executable_name;
+  p_bool "systhread_supported" systhread_supported;
+  p "host" host;
+  p "target" target;
+  p_bool "flambda" flambda;
+  p_bool "safe_string" safe_string;
+  p_bool "default_safe_string" default_safe_string;
+  p_bool "flat_float_array" flat_float_array;
+  p_bool "function_sections" function_sections;
+  p_bool "afl_instrument" afl_instrument;
+  p_bool "windows_unicode" windows_unicode;
+  p_bool "supports_shared_libraries" supports_shared_libraries;
+  p_bool "naked_pointers" naked_pointers;
+
+  p "exec_magic_number" exec_magic_number;
+  p "cmi_magic_number" cmi_magic_number;
+  p "cmo_magic_number" cmo_magic_number;
+  p "cma_magic_number" cma_magic_number;
+  p "cmx_magic_number" cmx_magic_number;
+  p "cmxa_magic_number" cmxa_magic_number;
+  p "ast_impl_magic_number" ast_impl_magic_number;
+  p "ast_intf_magic_number" ast_intf_magic_number;
+  p "cmxs_magic_number" cmxs_magic_number;
+  p "cmt_magic_number" cmt_magic_number;
+  p "linear_magic_number" linear_magic_number;
+]
+
+let print_config_value oc = function
+  | String s ->
+      Printf.fprintf oc "%s" s
+  | Int n ->
+      Printf.fprintf oc "%d" n
+  | Bool p ->
+      Printf.fprintf oc "%B" p
+
+let print_config oc =
+  let print (x, v) =
+    Printf.fprintf oc "%s: %a\n" x print_config_value v in
+  List.iter print configuration_variables;
+  flush oc
+
+let config_var x =
+  match List.assoc_opt x configuration_variables with
+  | None -> None
+  | Some v ->
+      let s = match v with
+        | String s -> s
+        | Int n -> Int.to_string n
+        | Bool b -> string_of_bool b
+      in
+      Some s
+
+let merlin = false
diff --git a/utils/config.fixed.ml b/utils/config.fixed.ml
new file mode 100644
index 0000000000..fce7c4621a
--- /dev/null
+++ b/utils/config.fixed.ml
@@ -0,0 +1,71 @@
+#2 "utils/config.fixed.ml"
+(**************************************************************************)
+(*                                                                        *)
+(*                                 OCaml                                  *)
+(*                                                                        *)
+(*                       David Allsopp, Tarides UK.                       *)
+(*                                                                        *)
+(*   Copyright 2022 David Allsopp Ltd.                                    *)
+(*                                                                        *)
+(*   All rights reserved.  This file is distributed under the terms of    *)
+(*   the GNU Lesser General Public License version 2.1, with the          *)
+(*   special exception on linking described in the file LICENSE.          *)
+(*                                                                        *)
+(**************************************************************************)
+
+(* Configuration for the boot compiler. The compiler should refuse to bootstrap
+   if configured with values which would contradict the configuration below.
+   Config.in_boot_compiler is used throughout the compiler to prevent accidental
+   use of "<boot compiler>" values, but should not be used to control
+   compilation decisions (i.e. if Config.in_boot_compiler is found to be true,
+   the result of the code path should be a fatal error) *)
+
+let bindir = "<boot compiler>"
+let standard_library_default = "<boot compiler>"
+let in_boot_compiler = true
+let ccomp_type = "<boot compiler>"
+let c_compiler = "<boot compiler>"
+let c_output_obj = "<boot compiler>"
+let c_has_debug_prefix_map = false
+let as_has_debug_prefix_map = false
+let ocamlc_cflags = "<boot compiler>"
+let ocamlc_cppflags = "<boot compiler>"
+let ocamlopt_cflags = "<boot compiler>"
+let ocamlopt_cppflags = "<boot compiler>"
+let bytecomp_c_libraries = "<boot compiler>"
+let bytecomp_c_compiler = "<boot compiler>"
+let native_c_compiler = "<boot compiler>"
+let native_c_libraries = "<boot compiler>"
+let native_pack_linker = "<boot compiler>"
+let default_rpath = "<boot compiler>"
+let mksharedlibrpath = "<boot compiler>"
+let ar = "<boot compiler>"
+let supports_shared_libraries = false
+let mkdll = "<boot compiler>"
+let mkexe = "<boot compiler>"
+let mkmaindll = "<boot compiler>"
+let flambda = false
+let with_flambda_invariants = false
+let with_cmm_invariants = false
+let windows_unicode = false
+let force_instrumented_runtime = false
+let flat_float_array = true
+let function_sections = false
+let afl_instrument = false
+let architecture = "none"
+let model = "default"
+let system = "unknown"
+let asm = "<boot compiler>"
+let asm_cfi_supported = false
+let with_frame_pointers = false
+let profinfo = false
+let profinfo_width = 0
+let ext_exe = "<boot compiler>"
+let ext_obj = "<boot compiler>"
+let ext_asm = "<boot compiler>"
+let ext_lib = "<boot compiler>"
+let ext_dll = "<boot compiler>"
+let host = "<boot compiler>"
+let target = "<boot compiler>"
+let systhread_supported = false
+let flexdll_dirs = []
diff --git a/utils/config.mlp b/utils/config.mlp
index 92261b6321..fd25cec69b 100644
--- a/utils/config.mlp
+++ b/utils/config.mlp
@@ -14,23 +14,11 @@
 (*                                                                        *)
 (**************************************************************************)
 
-(* The main OCaml version string has moved to ../build-aux/ocaml_version.m4 *)
-let version = Sys.ocaml_version
-
 let bindir = "%%BINDIR%%"
 
 let standard_library_default = "%%LIBDIR%%"
 
-let standard_library =
-  try
-    Sys.getenv "OCAMLLIB"
-  with Not_found ->
-  try
-    Sys.getenv "CAMLLIB"
-  with Not_found ->
-    standard_library_default
-
-let in_boot_compiler = %%IN_COREBOOT_CYCLE%%
+let in_boot_compiler = false
 
 let ccomp_type = "%%CCOMPTYPE%%"
 let c_compiler = "%%CC%%"
@@ -82,10 +70,7 @@ let mkdll, mkexe, mkmaindll =
 let flambda = %%FLAMBDA%%
 let with_flambda_invariants = %%WITH_FLAMBDA_INVARIANTS%%
 let with_cmm_invariants = %%WITH_CMM_INVARIANTS%%
-let safe_string = true
-let default_safe_string = true
 let windows_unicode = %%WINDOWS_UNICODE%% != 0
-let naked_pointers = false
 let force_instrumented_runtime = %%FORCE_INSTRUMENTED_RUNTIME%%
 
 let flat_float_array = %%FLAT_FLOAT_ARRAY%%
@@ -93,39 +78,6 @@ let flat_float_array = %%FLAT_FLOAT_ARRAY%%
 let function_sections = %%FUNCTION_SECTIONS%%
 let afl_instrument = %%AFL_INSTRUMENT%%
 
-let exec_magic_number = "Caml1999X031"
-    (* exec_magic_number is duplicated in runtime/caml/exec.h *)
-and cmi_magic_number = "Caml1999I031"
-and cmo_magic_number = "Caml1999O031"
-and cma_magic_number = "Caml1999A031"
-and cmx_magic_number =
-  if flambda then
-    "Caml1999y031"
-  else
-    "Caml1999Y031"
-and cmxa_magic_number =
-  if flambda then
-    "Caml1999z031"
-  else
-    "Caml1999Z031"
-and ast_impl_magic_number = "Caml1999M031"
-and ast_intf_magic_number = "Caml1999N031"
-and cmxs_magic_number = "Caml1999D031"
-and cmt_magic_number = "Caml1999T031"
-and linear_magic_number = "Caml1999L031"
-
-let interface_suffix = ref ".mli"
-
-let max_tag = 243
-(* This is normally the same as in obj.ml, but we have to define it
-   separately because it can differ when we're in the middle of a
-   bootstrapping phase. *)
-let lazy_tag = 246
-
-let max_young_wosize = 256
-let stack_threshold = 32 (* see runtime/caml/config.h *)
-let stack_safety_margin = 6
-
 let architecture = "%%ARCH%%"
 let model = "%%MODEL%%"
 let system = "%%SYSTEM%%"
@@ -145,104 +97,6 @@ let ext_dll = "%%EXT_DLL%%"
 let host = "%%HOST%%"
 let target = "%%TARGET%%"
 
-let default_executable_name =
-  match Sys.os_type with
-    "Unix" -> "a.out"
-  | "Win32" | "Cygwin" -> "camlprog.exe"
-  | _ -> "camlprog"
-
 let systhread_supported = %%SYSTHREAD_SUPPORT%%
 
 let flexdll_dirs = [%%FLEXDLL_DIR%%]
-
-type configuration_value =
-  | String of string
-  | Int of int
-  | Bool of bool
-
-let configuration_variables =
-  let p x v = (x, String v) in
-  let p_int x v = (x, Int v) in
-  let p_bool x v = (x, Bool v) in
-[
-  p "version" version;
-  p "standard_library_default" standard_library_default;
-  p "standard_library" standard_library;
-  p "ccomp_type" ccomp_type;
-  p "c_compiler" c_compiler;
-  p "ocamlc_cflags" ocamlc_cflags;
-  p "ocamlc_cppflags" ocamlc_cppflags;
-  p "ocamlopt_cflags" ocamlopt_cflags;
-  p "ocamlopt_cppflags" ocamlopt_cppflags;
-  p "bytecomp_c_compiler" bytecomp_c_compiler;
-  p "native_c_compiler" native_c_compiler;
-  p "bytecomp_c_libraries" bytecomp_c_libraries;
-  p "native_c_libraries" native_c_libraries;
-  p "native_pack_linker" native_pack_linker;
-  p "architecture" architecture;
-  p "model" model;
-  p_int "int_size" Sys.int_size;
-  p_int "word_size" Sys.word_size;
-  p "system" system;
-  p "asm" asm;
-  p_bool "asm_cfi_supported" asm_cfi_supported;
-  p_bool "with_frame_pointers" with_frame_pointers;
-  p "ext_exe" ext_exe;
-  p "ext_obj" ext_obj;
-  p "ext_asm" ext_asm;
-  p "ext_lib" ext_lib;
-  p "ext_dll" ext_dll;
-  p "os_type" Sys.os_type;
-  p "default_executable_name" default_executable_name;
-  p_bool "systhread_supported" systhread_supported;
-  p "host" host;
-  p "target" target;
-  p_bool "flambda" flambda;
-  p_bool "safe_string" safe_string;
-  p_bool "default_safe_string" default_safe_string;
-  p_bool "flat_float_array" flat_float_array;
-  p_bool "function_sections" function_sections;
-  p_bool "afl_instrument" afl_instrument;
-  p_bool "windows_unicode" windows_unicode;
-  p_bool "supports_shared_libraries" supports_shared_libraries;
-  p_bool "naked_pointers" naked_pointers;
-
-  p "exec_magic_number" exec_magic_number;
-  p "cmi_magic_number" cmi_magic_number;
-  p "cmo_magic_number" cmo_magic_number;
-  p "cma_magic_number" cma_magic_number;
-  p "cmx_magic_number" cmx_magic_number;
-  p "cmxa_magic_number" cmxa_magic_number;
-  p "ast_impl_magic_number" ast_impl_magic_number;
-  p "ast_intf_magic_number" ast_intf_magic_number;
-  p "cmxs_magic_number" cmxs_magic_number;
-  p "cmt_magic_number" cmt_magic_number;
-  p "linear_magic_number" linear_magic_number;
-]
-
-let print_config_value oc = function
-  | String s ->
-      Printf.fprintf oc "%s" s
-  | Int n ->
-      Printf.fprintf oc "%d" n
-  | Bool p ->
-      Printf.fprintf oc "%B" p
-
-let print_config oc =
-  let print (x, v) =
-    Printf.fprintf oc "%s: %a\n" x print_config_value v in
-  List.iter print configuration_variables;
-  flush oc
-
-let config_var x =
-  match List.assoc_opt x configuration_variables with
-  | None -> None
-  | Some v ->
-      let s = match v with
-        | String s -> s
-        | Int n -> Int.to_string n
-        | Bool b -> string_of_bool b
-      in
-      Some s
-
-let merlin = false