Added RELEASE var.

src/Makefile

@@ -8,8 +8,10 @@ CORE_SOURCES := \
 
 # Compiler and flags
 CORE_CC = gcc
-#CORE_CFLAGS = --std=c17 --pedantic -O3 -DASSET_FILE_NAME=\"$(ASSET_OUTPUT)\" $(shell pkg-config --cflags sdl2) # RELEASE
-CORE_CFLAGS = --std=c17 --pedantic -O1 -g -DASSET_FILE_NAME=\"$(ASSET_OUTPUT)\" $(shell pkg-config --cflags sdl2) \
+ifeq ($(RELEASE), 1)
+CORE_CFLAGS = --std=c17 --pedantic -O3 -DASSET_FILE_NAME=\"$(ASSET_OUTPUT)\" $(shell pkg-config --cflags sdl2) # RELEASE
+else
+CORE_CFLAGS = --std=c17 --pedantic -O0 -g -DASSET_FILE_NAME=\"$(ASSET_OUTPUT)\" $(shell pkg-config --cflags sdl2) \
 	-Wall -Wno-missing-braces -Wextra -Wno-missing-field-initializers \
     -Wformat=2 -Wswitch-default -Wswitch-enum -Wcast-align \
     -Wpointer-arith -Wbad-function-cast -Wstrict-overflow=5 \
@@ -17,6 +19,7 @@ CORE_CFLAGS = --std=c17 --pedantic -O1 -g -DASSET_FILE_NAME=\"$(ASSET_OUTPUT)\"
     -Wcast-qual -Wshadow -Wunreachable-code -Wlogical-op \
     -Wfloat-equal -Wstrict-aliasing=2 -Wredundant-decls \
     -Wold-style-definition # DEVELOPEMENT
+endif
 
 CORE_INCLUDE_DIRS = $(CORE_DIR)/headers
 CORE_INCLUDE_DIRS := $(addprefix -I, $(CORE_INCLUDE_DIRS))