The supplied makefile doesn't work on MacOS, because SDL2 is not found.

Here is a corrected makefile, maybe you can modify your makefile to work both on Windows and MacOS:

CC = clang -Wall -std=c99
CFLAGS = -arch arm64 -I/opt/homebrew/include -I/opt/homebrew/include/SDL2
LDFLAGS = -L/opt/homebrew/lib -lSDL2 -lSDL2_net
EXE = u64view

all: $(EXE)

SOURCE=*.c

$(EXE): $(SOURCE)
        $(CC) $(CFLAGS) -O2 $(SOURCE) -o $(EXE) $(LDFLAGS)

clean:
        rm -f $(EXE) *.o

If you want to compile this tool on MacOS you need:

• xcode installed (in Terminal: xcode-select --install)
• SDL2 installed (brew install sdl2)
• SDL2_NET installed (brew install sdl2_net)
• Clone the repository (git clone https://github.com/DusteDdk/u64view.git) and change to its directory (cd u64view)

Then it should work to compile it using "make" with the modified Makefile.

Edit:
You need to use TAB instead of blanks in the Makefile!