##############################################################################
## Older GCC configuration.
##
## This should work for GCC versions back to somewhere in the late 4.x
## series, such as what the older Raspbian on the Ultimate Flashback uses.
##
## If the -std flags below don't work, try -std=c99 and std=c++1y instead.
##############################################################################
ifneq ($(HAVE_00_COMPILER),1)
HAVE_00_COMPILER := 1

# Compile with "LTO=" to make a one-off compile w/out link time optimization.
LTO ?= -flto

# GCC-specific sanitizer flags.
# Add USE_SANI=1 to enable a sanitizer build.  Recommend 'make clean' first.
#
# Older GCC may not provide these, so be prepared to comment some out if
# you compile with USE_SANI=1.
ifeq ($(USE_SANI),1)
 SANI  = -fsanitize=address
 SANI += -fsanitize-address-use-after-scope
 SANI += -fsanitize=leak
 SANI += -fsanitize=undefined
 # Sanitizers don't seem quite compatible with LTO right now, at least on Mac.
 LTO =
 # Also disable overall static linking (other than static GCC libs).
 SLFLAGS = $(LFLAGS)
endif

CC       = gcc -std=gnu11
CXX      = g++ -std=gnu++14
CXXFLAGS = -fvisibility=hidden

CFLAGS   += -fno-common -ffunction-sections -fdata-sections
CXXFLAGS += -fno-common -ffunction-sections -fdata-sections

# For GCC, statically link in its compiler-specific libraries so we are
# more portable among Macs.
LFLAGS   += -static-libstdc++ -static-libgcc

# Aggressive optimization flags, unless you compile with DEBUG=1.
ifeq ($(DEBUG),1)
OPT_FLAGS = -ggdb3
else
OPT_FLAGS  = -O3 -fomit-frame-pointer -fprefetch-loop-arrays 
OPT_FLAGS += -fstrict-aliasing -funswitch-loops
endif

# Used when building the SDL1 plat/SDL1_osx_main.m file on Macintosh only.
WARN_M  = -Wall -W -Wextra -Wshadow -Wpointer-arith
WARN_M += -Wbad-function-cast -Wcast-qual -Wc++-compat
WARN_M += -Wmissing-declarations -Wmissing-prototypes
WARN_M += -Wstrict-prototypes -Wuninitialized
WARN_M += -Werror

# Used when compiling C files.
WARN    = -Wall -W -Wextra -Wshadow -Wpointer-arith
WARN   += -Wbad-function-cast -Wcast-qual -Wc++-compat
WARN   += -Wmissing-declarations -Wmissing-prototypes
WARN   += -Wstrict-prototypes -Wstrict-aliasing
WARN   += -Werror

# Used when compiling C++ files.
WARNXX  = -Wall -W -Wextra -Wshadow -Wpointer-arith
WARNXX += -Wcast-qual -Wsequence-point -Wc++11-compat
WARNXX += -Wstrict-aliasing -Wlogical-op -Wold-style-cast
WARNXX += -Werror

# Only used on MacOS.
MACOS_VERSION_MIN = 10.6.0

endif