From: Enrico Tassi <gareuselesinge@debian.org>, Sergei Golovan <sgolovan@debian.org>
Date: Wed, 06 May 2020 10:31:53 +0300
Subject: build system

--- a/Makefile
+++ b/Makefile
@@ -10,19 +10,20 @@
 # so take care if INSTALL_TOP is not an absolute path. See the local target.
 # You may want to make INSTALL_LMOD and INSTALL_CMOD consistent with
 # LUA_ROOT, LUA_LDIR, and LUA_CDIR in luaconf.h.
-INSTALL_TOP= /usr/local
+INSTALL_TOP= $(shell pwd)/debian/tmp/usr
 INSTALL_BIN= $(INSTALL_TOP)/bin
-INSTALL_INC= $(INSTALL_TOP)/include
-INSTALL_LIB= $(INSTALL_TOP)/lib
-INSTALL_MAN= $(INSTALL_TOP)/man/man1
+INSTALL_INC= $(INSTALL_TOP)/include/lua5.4/
+INSTALL_LIB= $(INSTALL_TOP)/lib/$(DEB_HOST_MULTIARCH)/
+INSTALL_MAN= $(INSTALL_TOP)/share/man/man1
 INSTALL_LMOD= $(INSTALL_TOP)/share/lua/$V
-INSTALL_CMOD= $(INSTALL_TOP)/lib/lua/$V
+INSTALL_CMOD= $(INSTALL_TOP)/lib/$(DEB_HOST_MULTIARCH)/lua/$V
 
 # How to install. If your install program does not support "-p", then
 # you may have to run ranlib on the installed liblua.a.
 INSTALL= install -p
 INSTALL_EXEC= $(INSTALL) -m 0755
 INSTALL_DATA= $(INSTALL) -m 0644
+INSTALL_LIBTOOL= $(LIBTOOL) --mode=install install -m 0644
 #
 # If you don't have "install" you can use "cp" instead.
 # INSTALL= cp -p
@@ -39,10 +40,10 @@
 PLATS= guess aix bsd c89 freebsd generic linux linux-readline macosx mingw posix solaris
 
 # What to install.
-TO_BIN= lua luac
+TO_BIN= lua$(V) luac$(V)
 TO_INC= lua.h luaconf.h lualib.h lauxlib.h lua.hpp
-TO_LIB= liblua.a
-TO_MAN= lua.1 luac.1
+TO_LIB= liblua$(V).la liblua$(V)-c++.la
+TO_MAN= lua$(V).1 luac$(V).1
 
 # Lua version and release.
 V= 5.4
@@ -52,13 +53,13 @@
 all:	$(PLAT)
 
 $(PLATS) help test clean:
-	@cd src && $(MAKE) $@
+	@cd src && $(MAKE) $@ V=$(V)
 
 install: dummy
 	cd src && $(MKDIR) $(INSTALL_BIN) $(INSTALL_INC) $(INSTALL_LIB) $(INSTALL_MAN) $(INSTALL_LMOD) $(INSTALL_CMOD)
 	cd src && $(INSTALL_EXEC) $(TO_BIN) $(INSTALL_BIN)
 	cd src && $(INSTALL_DATA) $(TO_INC) $(INSTALL_INC)
-	cd src && $(INSTALL_DATA) $(TO_LIB) $(INSTALL_LIB)
+	cd src && $(INSTALL_LIBTOOL) $(TO_LIB) $(INSTALL_LIB)
 	cd doc && $(INSTALL_DATA) $(TO_MAN) $(INSTALL_MAN)
 
 uninstall:
--- a/src/Makefile
+++ b/src/Makefile
@@ -7,7 +7,9 @@
 PLAT= guess
 
 CC= gcc -std=gnu99
-CFLAGS= -O2 -Wall -Wextra -DLUA_COMPAT_5_3 $(SYSCFLAGS) $(MYCFLAGS)
+CXX= g++
+CFLAGS= -Wall -Wextra -DLUA_COMPAT_5_3 $(SYSCFLAGS) $(MYCFLAGS)
+CXXFLAGS= -Wall -Wextra -DLUA_COMPAT_5_3 $(SYSCFLAGS) $(MYCXXFLAGS)
 LDFLAGS= $(SYSLDFLAGS) $(MYLDFLAGS)
 LIBS= -lm $(SYSLIBS) $(MYLIBS)
 
@@ -20,27 +22,47 @@
 SYSLDFLAGS=
 SYSLIBS=
 
-MYCFLAGS=
-MYLDFLAGS=
-MYLIBS=
+MYCFLAGS=$(shell dpkg-buildflags --get CFLAGS) $(shell dpkg-buildflags --get CPPFLAGS)
+MYCXXFLAGS=$(shell dpkg-buildflags --get CXXFLAGS) $(shell dpkg-buildflags --get CPPFLAGS)
+MYLDFLAGS=$(shell dpkg-buildflags --get LDFLAGS)
+MYLIBS=-ldl
 MYOBJS=
 
 # Special flags for compiler modules; -Os reduces code size.
 CMCFLAGS= 
 
+%.o : %.c
+	$(LIBTOOL) --mode=compile --tag=CC $(CC) $(CFLAGS) -c $< -o $@
+	$(LIBTOOL) --mode=compile --tag=CXX $(CXX) $(CFLAGS) -c $< -o $*-c++.o
+
+# Build the compiler code with -Os to make the binaries as small as possible
+# (see https://github.com/lua/lua/commit/6a10f03ff81606e567c6891a90d70066a03c686e)
+
+llex.o: llex.c
+	$(LIBTOOL) --mode=compile --tag=CC $(CC) $(CFLAGS) -Os -c $< -o $@
+	$(LIBTOOL) --mode=compile --tag=CXX $(CXX) $(CFLAGS) -Os -c $< -o $*-c++.o
+
+lparser.o: lparser.c
+	$(LIBTOOL) --mode=compile --tag=CC $(CC) $(CFLAGS) -Os -c $< -o $@
+	$(LIBTOOL) --mode=compile --tag=CXX $(CXX) $(CFLAGS) -Os -c $< -o $*-c++.o
+
+lcode.o: lcode.c
+	$(LIBTOOL) --mode=compile --tag=CC $(CC) $(CFLAGS) -Os -c $< -o $@
+	$(LIBTOOL) --mode=compile --tag=CXX $(CXX) $(CFLAGS) -Os -c $< -o $*-c++.o
+
 # == END OF USER SETTINGS -- NO NEED TO CHANGE ANYTHING BELOW THIS LINE =======
 
 PLATS= guess aix bsd c89 freebsd generic linux linux-readline macosx mingw posix solaris
 
-LUA_A=	liblua.a
+LUA_A=	liblua$(V).la liblua$(V)-c++.la
 CORE_O=	lapi.o lcode.o lctype.o ldebug.o ldo.o ldump.o lfunc.o lgc.o llex.o lmem.o lobject.o lopcodes.o lparser.o lstate.o lstring.o ltable.o ltm.o lundump.o lvm.o lzio.o
 LIB_O=	lauxlib.o lbaselib.o lcorolib.o ldblib.o liolib.o lmathlib.o loadlib.o loslib.o lstrlib.o ltablib.o lutf8lib.o linit.o
 BASE_O= $(CORE_O) $(LIB_O) $(MYOBJS)
 
-LUA_T=	lua
+LUA_T=	lua$(V)
 LUA_O=	lua.o
 
-LUAC_T=	luac
+LUAC_T=	luac$(V)
 LUAC_O=	luac.o
 
 ALL_O= $(BASE_O) $(LUA_O) $(LUAC_O)
@@ -57,17 +79,17 @@
 a:	$(ALL_A)
 
 $(LUA_A): $(BASE_O)
-	$(AR) $@ $(BASE_O)
-	$(RANLIB) $@
+	$(LIBTOOL) --mode=link --tag=CC  $(CC)  $(LDFLAGS) -lm -ldl $(BASE_O:.o=.lo)     -rpath /usr/lib/$(DEB_HOST_MULTIARCH) -version-info 0:0:0 -Wl,--version-script,../debian/version-script -o liblua$(V).la
+	$(LIBTOOL) --mode=link --tag=CXX $(CXX) $(LDFLAGS) -lm -ldl $(BASE_O:.o=-c++.lo) -rpath /usr/lib/$(DEB_HOST_MULTIARCH) -version-info 0:0:0 -Wl,--version-script,../debian/version-script -o liblua$(V)-c++.la
 
 $(LUA_T): $(LUA_O) $(LUA_A)
-	$(CC) -o $@ $(LDFLAGS) $(LUA_O) $(LUA_A) $(LIBS)
+	$(LIBTOOL) --mode=link --tag=CC $(CC) $(LDFLAGS) $(LIBS) -Wl,--version-script,../debian/version-script -static liblua$(V).la -Wl,-E lua.lo -o $@
 
 $(LUAC_T): $(LUAC_O) $(LUA_A)
-	$(CC) -o $@ $(LDFLAGS) $(LUAC_O) $(LUA_A) $(LIBS)
+	$(LIBTOOL) --mode=link --tag=CC $(CC) $(LDFLAGS) -Wl,--version-script,../debian/version-script -static liblua$(V).la luac.lo -o $@
 
 test:
-	./$(LUA_T) -v
+	$(LIBTOOL) --mode=execute -dlopen ./liblua$(V).la ./lua$(V) -v
 
 clean:
 	$(RM) $(ALL_T) $(ALL_O)
@@ -144,15 +166,6 @@
 .PHONY: all $(PLATS) help test clean default o a depend echo
 
 # Compiler modules may use special flags.
-llex.o:
-	$(CC) $(CFLAGS) $(CMCFLAGS) -c llex.c
-
-lparser.o:
-	$(CC) $(CFLAGS) $(CMCFLAGS) -c lparser.c
-
-lcode.o:
-	$(CC) $(CFLAGS) $(CMCFLAGS) -c lcode.c
-
 # DO NOT DELETE
 
 lapi.o: lapi.c lprefix.h lua.h luaconf.h lapi.h llimits.h lstate.h \