Makefile: Platform independent OS detectio

Makefile

@@ -7,45 +7,11 @@ endif
 # Set the number of jobs for parallel execution
 MAKEFLAGS += --jobs=$(NUM_PROCESSORS)
 
-
-
-# make \
-compile program
-# make all \
-compile and run program
-# make clean \
-removes executable, object files, saves, and docs
-
-# developer commands:
-# make docs \
-generates the html docs using Doxygen
-# make fix \
-formats the code using clang-format, commits, and pushes the changes
-# make goto \
-proceed several rounds automatically and print the price history graph
-# make msvc \
-compile the program using the Microsoft Visual C++ compiler
-# make check \
-check the code for formatting and static analysis issues
-
-# Edit C++ compiler name you want to use.
-CXX = g++
-
-INCLUDES = -Iinclude
-OUTPUT = stocksim
-CXXFLAGS += -Wall -Wextra -pedantic -std=c++17 -Werror -g \
-	-Wcast-qual -Wundef -mtune=generic -Wswitch -Wshadow -Wformat=2
-	# -Wconversion -Wfloat-equal
-	# -fsanitize=address -fsanitize=undefined
-
-# macOS uses clang++, which does not support these flag:
-# -Wduplicated-cond -Wduplicated-branches
-ifeq ($(CXX),g++)
-# do not change $(OS) to $(shell uname) because on Windows
-# it might be MinGW or MSYS2, not Windows_NT
-ifneq ($(OS),Darwin)
-CXXFLAGS += -Wduplicated-cond -Wduplicated-branches
-endif
+# Set the OS variable using uname
+ifeq ($(shell uname),)
+	OS := Windows_NT
+else
+	OS := $(shell uname)
 endif
 
 # eric15342335 will use the static flag on Windows.