Building shared libs issue

[senseyman]

Hello. guys!
I'm trying to build those source files to .so shared libs to use it in Golang, but have some issues.
Here is my Makefile

# Compiler settings
CC := gcc
CFLAGS := -std=c99 -no-pie -mavx2 -g -O3 -Wall -Wextra -Werror -fPIC -Wno-error=sign-compare -Wno-error=unused-parameter
ASMFLAGS := -fPIC

# Directories
SRCDIR := source/avx2
OBJDIR := obj
LIBDIR := lib

# Source files
CFILES := $(wildcard $(SRCDIR)/*.c)
SFILES := $(wildcard $(SRCDIR)/*.s)

# Object files
COBJECTS := $(patsubst $(SRCDIR)/%.c, $(OBJDIR)/%.o, $(CFILES))
SOBJECTS := $(patsubst $(SRCDIR)/%.s, $(OBJDIR)/%.o, $(SFILES))

# Shared library name
LIBRARY := libavx2.so

all: $(LIBDIR)/$(LIBRARY)

# Compile C files
$(OBJDIR)/%.o: $(SRCDIR)/%.c
	$(CC) $(CFLAGS) -c -o $@ $<

# Assemble S files
$(OBJDIR)/%.o: $(SRCDIR)/%.s
	$(CC) $(ASMFLAGS) -c -o $@ $<

# Build shared library
$(LIBDIR)/$(LIBRARY): $(COBJECTS) $(SOBJECTS)
	$(CC) -shared -Wl,-Bsymbolic-functions -Wl,-z,relro -o $@ $^


clean:
	rm -f $(OBJDIR)/*.o
	rm -f $(LIBDIR)/$(LIBRARY)

But when I run it, I have next errors:
/usr/bin/ld: obj/genfullchain8x.o: relocation R_X86_64_32S against symbol _rotate8' can not be used when making a shared object; recompile with -fPIC`

As you can see, I'm building .s files with flag -fPIC but the compiler still tells me that there is an issue.

Can you help me with it?

Would be awesome if you add some instruction and tech specs to your README how to use your library.