use camlp5 instead of camlp4 (see #8547)

is it really this simple?

Makefile

@@ -123,7 +123,7 @@ build_dirs:
 	@mkdir -p $(BUILD_DIRECTORIES)
 
 _build/src/syntax/grammar.ml:src/syntax/grammar.mly
-	camlp4o -impl $< -o $@
+	camlp5o -impl $< -o $@
 
 _build/src/compiler/version.ml: FORCE
 ifneq ($(ADD_REVISION),0)
@@ -211,7 +211,7 @@ uninstall:
 	rm -rf $(DESTDIR)$(INSTALL_STD_DIR)
 
 opam_install:
-	opam install $(OPAM_LIBS) camlp4 ocamlfind --yes
+	opam install $(OPAM_LIBS) camlp5 ocamlfind --yes
 
 # Dependencies
 

Makefile.win

@@ -34,7 +34,6 @@ endif
 
 ifdef FILTER
 CC_CMD=($(COMPILER) $(ALL_CFLAGS) -c $< 2>tmp.cmi && $(FILTER)) || ($(FILTER) && exit 1)
-CC_PARSER_CMD=($(COMPILER) -pp camlp4o $(ALL_CFLAGS) -c src/syntax/parser.ml 2>tmp.cmi && $(FILTER)) || ($(FILTER) && exit 1)
 endif
 
 PACKAGE_FILES=$(HAXE_OUTPUT) $(HAXELIB_OUTPUT) std _build "$$(cygcheck $(CURDIR)/$(HAXE_OUTPUT) | grep zlib1.dll | sed -e 's/^\s*//')" "$$(cygcheck $(CURDIR)/$(HAXE_OUTPUT) | grep libpcre-1.dll | sed -e 's/^\s*//')"

extra/azure-pipelines/build-linux.yml

@@ -16,7 +16,7 @@ jobs:
           set -ex
           sudo add-apt-repository ppa:avsm/ppa -y # provides newer version of OCaml and OPAM
           sudo apt-get update -qqy
-          sudo apt-get install -qqy ocaml-nox camlp4-extra opam libpcre3-dev zlib1g-dev libgtk2.0-dev ninja-build
+          sudo apt-get install -qqy ocaml-nox camlp5 opam libpcre3-dev zlib1g-dev libgtk2.0-dev ninja-build
         displayName: Install dependencies
       - template: install-neko-snapshot.yaml
         parameters:

opam

@@ -21,7 +21,7 @@ remove: [make "uninstall" "INSTALL_DIR=%{prefix}%"]
 depends: [
   "ocaml"               {>= "4.02"}
   "ocamlfind"           {build}
-  "camlp4"              {build}
+  "camlp5"              {build}
   "sedlex"              {build & <= "1.99.4"} #https://github.com/HaxeFoundation/haxe/issues/7958
   "ppx_tools_versioned" {build & != "5.2.1"} #https://github.com/alainfrisch/sedlex/issues/64
   "xml-light"           {build}

tests/Brewfile

@@ -1,5 +1,5 @@
 brew "ocaml"
-brew "camlp4"
+brew "camlp5"
 brew "opam"
 brew "ninja"
 brew "zlib"