Working on repl, not fully working yet, read more

After a few hours struggling with the linker, I've got the main.c file
running correctly, with caveats:

- must be executed from out/
- only building on linux for the moment
- no tests written yet

I will write some CI jobs to see if the repl works eventually.

source/makefile

@@ -0,0 +1,87 @@
+#compiler settings
+CC=gcc
+CFLAGS+=-g -Wall -Werror -Wno-unused-parameter -Wno-unused-function -Wno-unused-variable
+LIBS+=-lm
+LDFLAGS+=
+
+#directories
+SRC_ROOTDIR=..
+SRC_SOURCEDIR=.
+
+SRC_OUTDIR=$(SRC_ROOTDIR)/out
+SRC_OBJDIR=obj
+
+#file names
+SRC_SOURCEFILES=$(wildcard $(SRC_SOURCEDIR)/*.c)
+SRC_OBJFILES=$(addprefix $(SRC_OBJDIR)/,$(notdir $(SRC_SOURCEFILES:.c=.o)))
+SRC_TARGETNAME=Toy
+
+#TODO: fix windows & macos
+#SRC_LIBLINE is a fancy way of making the linker work correctly
+ifeq ($(shell uname),Linux)
+	SRC_TARGETEXT=.so
+	SRC_LIBLINE=-Wl,-rpath,. -Wl,--out-implib=$(SRC_OUTDIR)/lib$(SRC_TARGETNAME).a -Wl,--whole-archive $(SRC_OBJFILES) -Wl,--no-whole-archive
+	CFLAGS+=-fPIC
+# else ifeq ($(OS),Windows_NT)
+# 	SRC_TARGETEXT=.dll
+# 	SRC_LIBLINE=-Wl,-rpath,. -Wl,--out-implib=$(SRC_OUTDIR)/lib$(OUTNAME).dll.a -Wl,--export-all-symbols -Wl,--enable-auto-import -Wl,--whole-archive $(SRC_OBJFILES) -Wl,--no-whole-archive
+# else ifeq ($(shell uname),Darwin)
+# 	SRC_TARGETEXT=.dylib
+# 	SRC_LIBLINE=$(SRC_OBJFILES)
+else
+	@echo "Platform test failed - what platform is this?"
+	exit 1
+endif
+
+#build the object files, compile the test cases, and run
+all: clean build link
+
+#targets for each step
+.PHONY: build
+build: $(SRC_OUTDIR) $(SRC_OBJDIR) $(SRC_OBJFILES)
+
+.PHONY: link
+link: $(SRC_OUTDIR)
+	$(CC) -DTOY_EXPORT $(CFLAGS) -shared -o $(SRC_OUTDIR)/lib$(SRC_TARGETNAME)$(SRC_TARGETEXT) $(SRC_LIBLINE)
+
+#util targets
+$(SRC_OUTDIR):
+	mkdir $(SRC_OUTDIR)
+
+$(SRC_OBJDIR):
+	mkdir $(SRC_OBJDIR)
+
+#compilation steps
+$(SRC_OBJDIR)/%.o: $(SRC_SOURCEDIR)/%.c
+	$(CC) -c -o $@ $< $(addprefix -I,$(SRC_SOURCEDIR)) $(CFLAGS)	
+
+#util commands
+.PHONY: clean
+clean:
+ifeq ($(shell uname),Linux)
+	find . -type f -name '*.o' -delete
+	find . -type f -name '*.a' -delete
+	find . -type f -name '*.exe' -delete
+	find . -type f -name '*.dll' -delete
+	find . -type f -name '*.lib' -delete
+	find . -type f -name '*.so' -delete
+	find . -type f -name '*.dylib' -delete
+	find . -type d -name 'out' -delete
+	find . -type d -name 'obj' -delete
+else ifeq ($(OS),Windows_NT)
+	$(RM) *.o *.a *.exe *.dll *.lib *.so *.dylib
+	$(RM) out
+	$(RM) obj
+else ifeq ($(shell uname),Darwin)
+	find . -type f -name '*.o' -delete
+	find . -type f -name '*.a' -delete
+	find . -type f -name '*.exe' -delete
+	find . -type f -name '*.dll' -delete
+	find . -type f -name '*.lib' -delete
+	find . -type f -name '*.so' -delete
+	find . -type f -name '*.dylib' -delete
+	find . -type d -name 'out' -delete
+	find . -type d -name 'obj' -delete
+else
+	@echo "Deletion failed - what platform is this?"
+endif