Bring Makefile on par with yquake2:

* Make CFLAGS and LDFLAGS overrideable
* Correct architecture and operating system detection.
* Enforce FPU mode.
* Implement DEBUG.
* Pass LDFLAGS after the objects.

Closes #9, closes #10.

Makefile

@@ -14,24 +14,38 @@
 # - Linux                                               #
 # - Mac OS X                                            #
 # - OpenBSD                                             #
-# - Windows                                             # 
+# - Windows                                             #
 # ----------------------------------------------------- #
 
 # Detect the OS
 ifdef SystemRoot
-OSTYPE := Windows
+YQ2_OSTYPE ?= Windows
 else
-OSTYPE := $(shell uname -s)
+YQ2_OSTYPE ?= $(shell uname -s)
 endif
- 
+
 # Special case for MinGW
-ifneq (,$(findstring MINGW,$(OSTYPE)))
+ifneq (,$(findstring MINGW,$(YQ2_OSTYPE)))
-OSTYPE := Windows
+YQ2_OSTYPE := Windows
+endif
+
+# Detect the architecture
+ifeq ($(YQ2_OSTYPE), Windows)
+ifdef PROCESSOR_ARCHITEW6432
+# 64 bit Windows
+YQ2_ARCH ?= $(PROCESSOR_ARCHITEW6432)
+else
+# 32 bit Windows
+YQ2_ARCH ?= $(PROCESSOR_ARCHITECTURE)
+endif
+else
+# Normalize some abiguous YQ2_ARCH strings
+YQ2_ARCH ?= $(shell uname -m | sed -e 's/i.86/i386/' -e 's/amd64/x86_64/' -e 's/^arm.*/arm/')
 endif
 
 # On Windows / MinGW $(CC) is undefined by default.
 ifeq ($(YQ2_OSTYPE),Windows)
-CC := gcc
+CC ?= gcc
 endif
 
 # Detect the compiler
@@ -47,30 +61,32 @@ endif
 
 # ----------
 
-# Base CFLAGS. 
+# Base CFLAGS. These may be overridden by the environment.
-#
+# Highest supported optimizations are -O2, higher levels
-# -O2 are enough optimizations.
+# will likely break this crappy code.
-# 
+ifdef DEBUG
-# -fno-strict-aliasing since the source doesn't comply
+CFLAGS ?= -O0 -g -Wall -pipe
-#  with strict aliasing rules and it's next to impossible
-#  to get it there...
-#
-# -fomit-frame-pointer since the framepointer is mostly
-#  useless for debugging Quake II and slows things down.
-#
-# -g to build allways with debug symbols. Please do not
-#  change this, since it's our only chance to debug this
-#  crap when random crashes happen!
-#
-# -fPIC for position independend code.
-#
-# -MMD to generate header dependencies.
-ifeq ($(OSTYPE), Darwin)
-CFLAGS := -O2 -fno-strict-aliasing -fomit-frame-pointer \
-		  -Wall -pipe -g -fwrapv -arch x86_64
 else
-CFLAGS := -O2 -fno-strict-aliasing -fomit-frame-pointer \
+CFLAGS ?= -O2 -Wall -pipe -fomit-frame-pointer
-		  -Wall -pipe -g -MMD -fwrapv
+endif
+
+# Always needed are:
+#  -fno-strict-aliasing since the source doesn't comply
+#   with strict aliasing rules and it's next to impossible
+#   to get it there...
+#  -fwrapv for defined integer wrapping. MSVC6 did this
+#   and the game code requires it.
+override CFLAGS += -std=gnu99 -fno-strict-aliasing -fwrapv
+
+# -MMD to generate header dependencies. Unsupported by
+#  the Clang shipped with OS X.
+ifneq ($(YQ2_OSTYPE), Darwin)
+override CFLAGS += -MMD
+endif
+
+# OS X architecture.
+ifeq ($(YQ2_OSTYPE), Darwin)
+override CFLAGS += -arch $(YQ2_ARCH)
 endif
 
 # ----------
@@ -91,20 +107,49 @@ endif
 
 # ----------
 
-# Base LDFLAGS.
+# Defines the operating system and architecture
-ifeq ($(OSTYPE), Darwin)
+override CFLAGS += -DYQ2OSTYPE=\"$(YQ2_OSTYPE)\" -DYQ2ARCH=\"$(YQ2_ARCH)\"
-LDFLAGS := -shared -arch x86_64
+
-else ifeq ($(OSTYPE), Windows)
+# ----------
-LDFLAGS := -shared -static-libgcc
+
-else
+# For reproduceable builds, look here for details:
-LDFLAGS := -shared -lm
+# https://reproducible-builds.org/specs/source-date-epoch/
+ifdef SOURCE_DATE_EPOCH
+CFLAGS += -DBUILD_DATE=\"$(shell date --utc --date="@${SOURCE_DATE_EPOCH}" +"%b %_d %Y" | sed -e 's/ /\\ /g')\"
 endif
 
 # ----------
 
-# https://reproducible-builds.org/specs/source-date-epoch/
+# If we're building with gcc for i386 let's define -ffloat-store.
-ifdef SOURCE_DATE_EPOCH
+# This helps the old and crappy x87 FPU to produce correct values.
-CFLAGS += -DBUILD_DATE=\"$(shell date --utc --date="@${SOURCE_DATE_EPOCH}" +"%b %_d %Y" | sed -e 's/ /\\ /g')\"
+# Would be nice if Clang had something comparable.
+ifeq ($(YQ2_ARCH), i386)
+ifeq ($(COMPILER), gcc)
+override CFLAGS += -ffloat-store
+endif
+endif
+
+# Force SSE math on x86_64. All sane compilers should do this
+# anyway, just to protect us from broken Linux distros.
+ifeq ($(YQ2_ARCH), x86_64)
+override CFLAGS += -mfpmath=sse
+endif
+
+# ----------
+
+# Base LDFLAGS.
+LDFLAGS ?=
+
+# It's a shared library.
+override LDFLAGS += -shared
+
+# Required libaries
+ifeq ($(YQ2_OSTYPE), Darwin)
+override LDFLAGS += -arch $(YQ2_ARCH)
+else ifeq ($(OSTYPE), Windows)
+override LDFLAGS += -static-libgcc
+else
+override LDFLAGS += -lm
 endif
 
 # ----------
@@ -113,7 +158,7 @@ endif
 all: ctf
 
 # ----------
- 
+
 # When make is invoked by "make VERBOSE=1" print
 # the compiler and linker commands.
 
@@ -129,12 +174,12 @@ endif
 .PHONY : all clean ctf
 
 # ----------
- 
+
 # Cleanup
 clean:
 	@echo "===> CLEAN"
 	${Q}rm -Rf build release
- 
+
 # ----------
 
 # The ctf game
@@ -156,7 +201,7 @@ ctf:
 
 release/game.so : CFLAGS += -fPIC
 endif
- 
+
 build/%.o: %.c
 	@echo "===> CC $<"
 	$(Q)mkdir -p $(@D)
@@ -190,7 +235,7 @@ CTF_OBJS_ = \
 	src/player/trail.o \
 	src/player/view.o \
 	src/player/weapon.o \
-	src/shared/shared.o 
+	src/shared/shared.o
 
 # ----------
 
@@ -209,18 +254,18 @@ CTF_DEPS= $(CTF_OBJS:.o=.d)
 
 # ----------
 
-ifeq ($(OSTYPE), Windows)
+ifeq ($(YQ2_OSTYPE), Windows)
 release/game.dll : $(CTF_OBJS)
 	@echo "===> LD $@"
-	$(Q)$(CC) $(LDFLAGS) -o $@ $(CTF_OBJS)
+	$(Q)$(CC) -o $@ $(CTF_OBJS) $(LDFLAGS)
-else ifeq ($(OSTYPE), Darwin)
+else ifeq ($(YQ2_OSTYPE), Darwin)
 release/game.dylib : $(CTF_OBJS)
 	@echo "===> LD $@"
-	${Q}$(CC) $(LDFLAGS) -o $@ $(CTF_OBJS)
+	${Q}$(CC) -o $@ $(CTF_OBJS) $(LDFLAGS)
 else
 release/game.so : $(CTF_OBJS)
 	@echo "===> LD $@"
-	$(Q)$(CC) $(LDFLAGS) -o $@ $(CTF_OBJS)
+	$(Q)$(CC) -o $@ $(CTF_OBJS) $(LDFLAGS)
 endif
- 
+
 # ----------