Update build procedure

.gitignore

@@ -6,3 +6,4 @@
 options.inc
 core
 ld
+oneTBB

.gitmodules

@@ -1,9 +1,3 @@
-[submodule "oneTBB"]
-	path = oneTBB
-	url = https://github.com/oneapi-src/oneTBB.git
 [submodule "mimalloc"]
 	path = mimalloc
 	url = https://github.com/microsoft/mimalloc.git
-[submodule "xxHash"]
-	path = xxHash
-	url = https://github.com/Cyan4973/xxHash.git

Makefile

@@ -1,29 +1,25 @@
-CC=clang
-CXX=clang++
-
-CURRENT_DIR=$(shell pwd)
-TBB_LIBDIR=$(wildcard $(CURRENT_DIR)/oneTBB/build/linux_intel64_*_release/)
-MALLOC_LIBDIR=$(CURRENT_DIR)/mimalloc/out/release
-
-CPPFLAGS=-g -IoneTBB/include -IxxHash -pthread -std=c++20 \
-         -Wno-deprecated-volatile -Wno-switch \
-         -DGIT_HASH=\"$(shell git rev-parse HEAD)\"
-LDFLAGS=-fuse-ld=lld -L$(TBB_LIBDIR) -Wl,-rpath=$(TBB_LIBDIR) \
-        -L$(MALLOC_LIBDIR) -Wl,-rpath=$(MALLOC_LIBDIR) \
-        -L$(CURRENT_DIR)/xxHash -Wl,-rpath=$(CURRENT_DIR)/xxHash
-LIBS=-lcrypto -pthread -ltbb -lmimalloc -lz -lxxhash -ldl
-OBJS=main.o object_file.o input_sections.o output_chunks.o mapfile.o perf.o \
-     linker_script.o archive_file.o output_file.o subprocess.o gc_sections.o \
-     icf.o symbols.o cmdline.o filepath.o glob.o passes.o tar.o compress.o \
-     arch_x86_64.o arch_i386.o
+CC = clang
+CXX = clang++
+
+MIMALLOC_LIB = mimalloc/out/release/libmimalloc.a
+
+CPPFLAGS = -g -Imimalloc/include -pthread -std=c++20 \
+           -Wno-deprecated-volatile -Wno-switch \
+           -DGIT_HASH=\"$(shell git rev-parse HEAD)\" \
+	   $(EXTRA_CPPFLAGS)
+LDFLAGS = $(EXTRA_LDFLAGS)
+LIBS = -lcrypto -pthread -ltbb -lz -lxxhash \
+       -Wl,-as-needed -ldl -Wl,-no-as-needed
+OBJS = main.o object_file.o input_sections.o output_chunks.o \
+       mapfile.o perf.o linker_script.o archive_file.o output_file.o \
+       subprocess.o gc_sections.o icf.o symbols.o cmdline.o filepath.o \
+       glob.o passes.o tar.o compress.o arch_x86_64.o arch_i386.o
 
 PREFIX ?= /usr
-
 DEBUG ?= 0
 LTO ?= 0
 ASAN ?= 0
 TSAN ?= 0
-STATIC ?= 1
 
 ifeq ($(DEBUG), 1)
   CPPFLAGS += -O0
@@ -39,36 +35,32 @@ endif
 ifeq ($(ASAN), 1)
   CPPFLAGS += -fsanitize=address
   LDFLAGS  += -fsanitize=address
-  STATIC    = 0
+else
+  # By default, we want to use mimalloc as a memory allocator.
+  # Since replacing the standard malloc is not compatible with ASAN,
+  # we do that only when ASAN is not enabled.
+  LDFLAGS += -Wl,-whole-archive $(MIMALLOC_LIB) -Wl,-no-whole-archive
 endif
 
 ifeq ($(TSAN), 1)
   CPPFLAGS += -fsanitize=thread
   LDFLAGS  += -fsanitize=thread
-  STATIC    = 0
-endif
-
-ifeq ($(STATIC), 1)
-  CPPFLAGS += -static
 endif
 
 all: mold mold-wrapper.so
 
-mold: $(OBJS)
+mold: $(OBJS) $(MIMALLOC_LIB)
 	$(CXX) $(CFLAGS) $(OBJS) -o $@ $(LDFLAGS) $(LIBS)
 
 mold-wrapper.so: mold-wrapper.c Makefile
 	cc -fPIC -shared -o $@ $< -ldl
 
 $(OBJS): mold.h elf.h Makefile
 
-submodules:
-	$(MAKE) -C oneTBB
-	$(MAKE) -C oneTBB extra_inc=big_iron.inc
+$(MIMALLOC_LIB):
 	mkdir -p mimalloc/out/release
 	(cd mimalloc/out/release; CFLAGS=-DMI_USE_ENVIRON=0 cmake ../..)
 	$(MAKE) -C mimalloc/out/release
-	$(MAKE) -C xxHash
 
 test: all
 	for i in test/*.sh; do $$i || exit 1; done

README.md

@@ -62,20 +62,19 @@ Clang. I'm using Ubuntu 20.04 as a development platform. In that
 environment, you can build mold by the following commands.
 
 ```
-$ sudo apt-get install build-essential libstdc++-10-dev clang-10 libssl-dev zlib1g-dev cmake
+$ sudo apt-get install build-essential libstdc++-10-dev cmake clang libssl-dev zlib1g-dev libxxhash-dev libtbb-dev
 $ git clone --recursive https://github.com/rui314/mold.git
 $ cd mold
-$ make submodules
 $ make
 ```
 
 The last `make` command creates `mold` executable.
 
-You can build a statically-linked mold executable by substituting the
-last `make` with `make STATIC=1`. A statically-linked mold executable
-can be copied to any Linux system and run there without copying other
-libraries. This is useful if you want to use Ubuntu 20.04 only for
-building mold.
+If you don't have Ubuntu 20.04, or if for any reason `make` in the
+above commands doesn't work for you, you can use Docker to build it in
+a Docker environment. To do so, just run `./build-static.sh` in this
+directory. The script creates a Ubuntu 20.04 Docker image, install
+necessary tools and libraries to it and build mold as a static binary.
 
 ## How to use
 

build-static.sh

@@ -0,0 +1,33 @@
+#!/bin/bash -x
+
+# This is a shell script to build a statically-linked mold
+# executable using Docker, so that it is easy to build mold
+# on non-Ubuntu 20.04 machines.
+#
+# A docker image used for building mold is persistent.
+# Run `docker image rm mold-build-ubuntu20` to remove the image
+# from disk.
+
+cat <<EOF | docker build -t mold-build-ubuntu20 -
+FROM ubuntu:20.04
+RUN apt-get update && \
+  TZ=Europe/London apt-get install -y tzdata && \
+  apt-get install -y build-essential git clang lld cmake \
+    libstdc++-10-dev libxxhash-dev zlib1g-dev libssl-dev && \
+  rm -rf /var/lib/apt/lists/*
+EOF
+
+if ! [ -d oneTBB ]; then
+  git clone https://github.com/oneapi-src/oneTBB.git
+  (cd oneTBB; git checkout --quiet v2020.3)
+fi
+
+docker run -it --rm -v `pwd`/oneTBB:/oneTBB -u $(id -u):$(id -g) \
+  mold-build-ubuntu20 \
+  make -C /oneTBB -j$(nproc) extra_inc=big_iron.inc
+
+docker run -it --rm -v `pwd`/oneTBB:/oneTBB -v `pwd`:/mold \
+  -u $(id -u):$(id -g) mold-build-ubuntu20 \
+  make EXTRA_CPPFLAGS=-I/oneTBB/include \
+       EXTRA_LDFLAGS="-fuse-ld=lld -static -L/$(ls -d oneTBB/build/linux_intel64_*_release)" \
+       -j$(nproc) -C /mold

mold.h

@@ -5,7 +5,6 @@
 #endif
 
 #include "elf.h"
-#include "xxHash/xxhash.h"
 
 #include <atomic>
 #include <cassert>
@@ -27,6 +26,7 @@
 #include <tbb/task_group.h>
 #include <unordered_set>
 #include <vector>
+#include <xxh3.h>
 
 typedef uint8_t u8;
 typedef uint16_t u16;