Bug 1182727 - Part 4: Add support for configurable three stage builds; r=rail

This adds a stages config option, which can be used to select 1, 2, and
3 stage builds.  It also marks the default trunk configuration to do 3
stage builds, and defaults to that.

build/unix/build-clang/build-clang.py

@@ -55,7 +55,9 @@ def updated_env(env):
 
 def build_tar_package(tar, name, base, directory):
     name = os.path.realpath(name)
-    run_in(base, [tar, "-cJf", name, directory])
+    run_in(base, [tar,
+                  "-c -%s -f" % "J" if ".xz" in name else "j",
+                  name, directory])
 
 
 def copy_dir_contents(src, dest):
@@ -202,6 +204,11 @@ if __name__ == "__main__":
     clang_repo = config["clang_repo"]
     compiler_repo = config["compiler_repo"]
     libcxx_repo = config["libcxx_repo"]
+    stages = 3
+    if "stages" in config:
+        stages = int(config["stages"])
+        if stages not in (1, 2, 3):
+            raise ValueError("We only know how to build 1, 2, or 3 stages")
 
     if not os.path.exists(source_dir):
         os.makedirs(source_dir)
@@ -228,6 +235,8 @@ if __name__ == "__main__":
     stage1_dir = build_dir + '/stage1'
     stage1_inst_dir = stage1_dir + '/clang'
 
+    final_stage_dir = stage1_dir
+
     if is_darwin():
         extra_cflags = ""
         extra_cxxflags = "-stdlib=libc++"
@@ -255,17 +264,31 @@ if __name__ == "__main__":
          "CXX": cxx + " %s" % extra_cxxflags},
         llvm_source_dir, stage1_dir, build_libcxx)
 
-    stage2_dir = build_dir + '/stage2'
-    build_one_stage(
-        {"CC": stage1_inst_dir + "/bin/clang %s" % extra_cflags2,
-         "CXX": stage1_inst_dir + "/bin/clang++ %s" % extra_cxxflags2},
-        llvm_source_dir, stage2_dir, build_libcxx)
+    if stages > 1:
+        stage2_dir = build_dir + '/stage2'
+        stage2_inst_dir = stage2_dir + '/clang'
+        final_stage_dir = stage2_dir
+        build_one_stage(
+            {"CC": stage1_inst_dir + "/bin/clang %s" % extra_cflags2,
+             "CXX": stage1_inst_dir + "/bin/clang++ %s" % extra_cxxflags2},
+            llvm_source_dir, stage2_dir, build_libcxx)
+
+        if stages > 2:
+            stage3_dir = build_dir + '/stage3'
+            final_stage_dir = stage3_dir
+            build_one_stage(
+                {"CC": stage2_inst_dir + "/bin/clang %s" % extra_cflags2,
+                 "CXX": stage2_inst_dir + "/bin/clang++ %s" % extra_cxxflags2},
+                llvm_source_dir, stage3_dir, build_libcxx)
 
     if not is_darwin():
-        stage2_inst_dir = stage2_dir + '/clang'
+        final_stage_inst_dir = final_stage_dir + '/clang'
         build_and_use_libgcc(
             {"CC": cc + " %s" % extra_cflags,
              "CXX": cxx + " %s" % extra_cxxflags},
-            stage2_inst_dir)
+            final_stage_inst_dir)
 
-    build_tar_package("tar", "clang.tar.xz", stage2_dir, "clang")
+    if is_darwin():
+        build_tar_package("tar", "clang.tar.bz2", final_stage_dir, "clang")
+    else:
+        build_tar_package("tar", "clang.tar.xz", final_stage_dir, "clang")

build/unix/build-clang/clang-trunk.json

@@ -1,5 +1,6 @@
 {
     "llvm_revision": "247539",
+    "stages": "3",
     "llvm_repo": "https://llvm.org/svn/llvm-project/llvm/trunk",
     "clang_repo": "https://llvm.org/svn/llvm-project/cfe/trunk",
     "compiler_repo": "https://llvm.org/svn/llvm-project/compiler-rt/trunk",