IfcOpenShell WASM module build script (#2617)

cmake/CMakeLists.txt

@@ -54,6 +54,7 @@ OPTION(USE_VLD "Use Visual Leak Detector for debugging memory leaks, MSVC-only."
 OPTION(USE_MMAP "Adds a command line options to parse IFC files from memory mapped files using Boost.Iostreams" OFF)
 OPTION(BUILD_SHARED_LIBS "Build IfcParse and IfcGeom as shared libs (SO/DLL)." OFF)
 OPTION(MSVC_PARALLEL_BUILD "Multi-threaded compilation in Microsoft Visual Studio (/MP)" OFF)
+OPTION(WASM_BUILD OFF)
 if (${HAS_MAX})
 OPTION(BUILD_IFCMAX "Build IfcMax, a 3ds Max plug-in, Windows-only." OFF)
 endif()
@@ -149,6 +150,14 @@ UNIFY_ENVVARS_AND_CACHE(MPFR_INCLUDE_DIR)
 UNIFY_ENVVARS_AND_CACHE(MPFR_LIBRARY_DIR)
 endif()
 
+if(WASM_BUILD)
+    # when using the nix/build-all.py build script we should not
+    # look into the sysroot for most of the dependencies but rather
+    # in the designated build/ folder created by the script.
+    set(CMAKE_FIND_ROOT_PATH_BACKUP "${CMAKE_FIND_ROOT_PATH}")
+    set(CMAKE_FIND_ROOT_PATH "")
+endif()
+
 if (NOT MINIMAL_BUILD AND GLTF_SUPPORT AND BUILD_CONVERT)
 UNIFY_ENVVARS_AND_CACHE(JSON_INCLUDE_DIR)
 FIND_FILE(json_hpp "json.hpp" ${JSON_INCLUDE_DIR}/nlohmann)
@@ -199,7 +208,14 @@ ELSE()
     ENDIF()
 ENDIF()
 
-set(BOOST_COMPONENTS system program_options regex thread date_time)
+if (WASM_BUILD)
+    set(BOOST_COMPONENTS)
+else()
+    # @todo review this, shouldn't this be all possible header-only now?
+    # ... or rewritten using C++17 features?
+    set(BOOST_COMPONENTS system program_options regex thread date_time)
+endif()
+
 if(USE_MMAP)
     if(MSVC)
         # filesystem is necessary for the utf-16 wpath
@@ -210,6 +226,10 @@ if(USE_MMAP)
     add_definitions(-DUSE_MMAP)
 endif()
 
+FIND_PACKAGE(Boost REQUIRED COMPONENTS ${BOOST_COMPONENTS})
+MESSAGE(STATUS "Boost include files found in ${Boost_INCLUDE_DIRS}")
+MESSAGE(STATUS "Boost libraries found in ${Boost_LIBRARY_DIRS}")
+
 if (NOT MINIMAL_BUILD)
 # libxml2 is required for IFCXML (optional) and SVGFILL (mandatory)
   find_package(LibXml2 REQUIRED)
@@ -220,11 +240,6 @@ if (NOT MINIMAL_BUILD AND IFCXML_SUPPORT)
 	set(SWIG_DEFINES ${SWIG_DEFINES} -DWITH_IFCXML)
 endif()
 
-FIND_PACKAGE(Boost REQUIRED COMPONENTS ${BOOST_COMPONENTS})
-MESSAGE(STATUS "Boost include files found in ${Boost_INCLUDE_DIRS}")
-MESSAGE(STATUS "Boost libraries found in ${Boost_LIBRARY_DIRS}")
-
-
 # Usage:
 # set(SOME_LIRARIES foo bar)
 # add_debug_variants(SOME_LIRARIES "${SOME_LIRARIES}" d)
@@ -343,10 +358,21 @@ if("${libTKernelExt}" STREQUAL ".a")
     set(OCCT_STATIC ON)
 endif()
 
+if(WASM_BUILD)
+    set(CMAKE_FIND_ROOT_PATH "${CMAKE_FIND_ROOT_PATH_BACKUP}")
+endif()
+
 if(OCCT_STATIC)
     find_package(Threads)
-    # OPENCASCADE_LIBRARIES repeated three times below in order to fix cyclic dependencies - use --start-group ... --end-group instead?
+    
-    set(OPENCASCADE_LIBRARIES ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+    if(WASM_BUILD)
+        set(OPENCASCADE_LIBRARIES ${OPENCASCADE_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+    else()
+        # OPENCASCADE_LIBRARIES repeated N times below in order to fix cyclic dependencies - use --start-group ... --end-group instead?
+        # tfk: --start-group ... --end-group didn't work on the apple linker when last tested
+        set(OPENCASCADE_LIBRARIES ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${OPENCASCADE_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+    endif()
+    
     if (NOT APPLE AND NOT WIN32)
         set(OPENCASCADE_LIBRARIES ${OPENCASCADE_LIBRARIES} "rt")
     endif()
@@ -620,7 +646,12 @@ function(files_for_ifc_version IFC_VERSION RESULT_NAME)
 endfunction()
 
 if(NOT SCHEMA_VERSIONS)
-    set(SCHEMA_VERSIONS "2x3" "4" "4x1" "4x2" "4x3_rc1" "4x3_rc2" "4x3_rc3" "4x3_rc4" "4x3" "4x3_tc1" "4x3_add1")
+    if(WASM_BUILD)
+        # super arbitrarily try to keep size down at least a little bit
+        set(SCHEMA_VERSIONS "2x3" "4")
+    else()
+        set(SCHEMA_VERSIONS "2x3" "4" "4x1" "4x2" "4x3_rc1" "4x3_rc2" "4x3_rc3" "4x3_rc4" "4x3" "4x3_tc1" "4x3_add1")
+    endif()
 endif()
 
 foreach(s ${SCHEMA_VERSIONS})
@@ -697,7 +728,11 @@ if (BUILD_IFCGEOM)
 	foreach(s ${SCHEMA_VERSIONS})
 		set(IFCGEOM_SCHEMA_LIBRARIES ${IFCGEOM_SCHEMA_LIBRARIES} IfcGeom_ifc${s})
 	endforeach()
-	set(IFCOPENSHELL_LIBRARIES ${IFCOPENSHELL_LIBRARIES} IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES} IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES})
+	if (WASM_BUILD)
+	    set(IFCOPENSHELL_LIBRARIES ${IFCOPENSHELL_LIBRARIES} IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES})
+	else()
+	    set(IFCOPENSHELL_LIBRARIES ${IFCOPENSHELL_LIBRARIES} IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES} IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES})	
+	endif()
 endif()
 if (BUILD_CONVERT OR BUILD_IFCPYTHON)
 	foreach(s ${SCHEMA_VERSIONS})
@@ -741,7 +776,11 @@ set(IFCPARSE_FILES ${IFCPARSE_CPP_FILES} ${IFCPARSE_H_FILES})
 add_library(IfcParse ${IFCPARSE_FILES})
 set_target_properties(IfcParse PROPERTIES COMPILE_FLAGS -DIFC_PARSE_EXPORTS VERSION "0.6.0" SOVERSION "0.6")
 
-TARGET_LINK_LIBRARIES(IfcParse ${Boost_LIBRARIES} ${BCRYPT_LIBRARIES} ${LIBXML2_LIBRARIES})
+if (WASM_BUILD)
+    TARGET_LINK_LIBRARIES(IfcParse ${BCRYPT_LIBRARIES} ${LIBXML2_LIBRARIES})
+else()
+    TARGET_LINK_LIBRARIES(IfcParse ${Boost_LIBRARIES} ${BCRYPT_LIBRARIES} ${LIBXML2_LIBRARIES})
+endif()
 
 if (BUILD_IFCGEOM)
 
@@ -753,7 +792,9 @@ set(IFCGEOM_FILES ${IFCGEOM_CPP_FILES} ${IFCGEOM_H_FILES})
 foreach(s ${SCHEMA_VERSIONS})
 	add_library(IfcGeom_ifc${s} STATIC ${IFCGEOM_FILES})
 	set_target_properties(IfcGeom_ifc${s} PROPERTIES COMPILE_FLAGS "-DIFC_GEOM_EXPORTS -DIfcSchema=Ifc${s}")
-	TARGET_LINK_LIBRARIES(IfcGeom_ifc${s} IfcParse ${OPENCASCADE_LIBRARIES})
+	if (NOT WASM_BUILD)
+	    TARGET_LINK_LIBRARIES(IfcGeom_ifc${s} IfcParse ${OPENCASCADE_LIBRARIES})	    
+	endif()
 endforeach()
 
 # IfcGeom (schema agnostic)
@@ -768,7 +809,11 @@ if (UNIX)
 find_package(Threads)
 endif()
 
-TARGET_LINK_LIBRARIES(IfcGeom IfcParse ${IFCGEOM_SCHEMA_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+if (WASM_BUILD)
+    TARGET_LINK_LIBRARIES(IfcGeom ${IFCGEOM_SCHEMA_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+else()
+    TARGET_LINK_LIBRARIES(IfcGeom IfcParse ${IFCGEOM_SCHEMA_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT})
+endif()
 
 endif(BUILD_IFCGEOM)
 
@@ -785,7 +830,12 @@ set(SERIALIZERS_S_FILES ${SERIALIZERS_S_H_FILES} ${SERIALIZERS_S_CPP_FILES})
 foreach(s ${SCHEMA_VERSIONS})
 	add_library(Serializers_ifc${s} STATIC ${SERIALIZERS_S_FILES})
 	set_target_properties(Serializers_ifc${s} PROPERTIES COMPILE_FLAGS "-DIFC_GEOM_EXPORTS -DIfcSchema=Ifc${s} ${CONVERT_PRECISION}")
-	TARGET_LINK_LIBRARIES(Serializers_ifc${s} IfcGeom ${OPENCASCADE_LIBRARIES} ${HDF5_LIBRARIES})
+	
+	if (WASM_BUILD)
+	    TARGET_LINK_LIBRARIES(Serializers_ifc${s} ${HDF5_LIBRARIES})
+	else()
+	    TARGET_LINK_LIBRARIES(Serializers_ifc${s} IfcGeom ${OPENCASCADE_LIBRARIES} ${HDF5_LIBRARIES})
+	endif()
 endforeach()
 
 add_library(Serializers ${SERIALIZERS_FILES})

nix/build-all.py

@@ -26,7 +26,7 @@
 #     * cmake * git * bzip2 * tar * c(++) compilers * autoconf                #
 #                                                                             #
 #   if building with USE_OCCT additionally:                                   #
-#     * freetype * glx.h                                                      #
+#     * glx.h                                                                 #
 #                                                                             #
 #   if building with OCCT 7.4.0 additionally:                                 #
 #     * libfontconfig1-dev                                                    #
@@ -39,14 +39,14 @@
 #                                                                             #
 #     on debian 7.8 these can be obtained with:                               #
 #          $ apt-get install git gcc g++ autoconf bison bzip2 cmake           #
-#            libfreetype6-dev mesa-common-dev libffi-dev libfontconfig1-dev   #
+#            mesa-common-dev libffi-dev libfontconfig1-dev                    #
 #                                                                             #
 #     on ubuntu 14.04:                                                        #
 #          $ apt-get install git gcc g++ autoconf bison make cmake            #
-#            libfreetype6-dev mesa-common-dev libffi-dev libfontconfig1-dev   #
+#            mesa-common-dev libffi-dev libfontconfig1-dev                    #
 #                                                                             #
 #     on OS X El Capitan with homebrew:                                       #
-#          $ brew install git bison autoconf automake freetype libffi cmake   #
+#          $ brew install git bison autoconf automake libffi cmake            #
 #                                                                             #
 ###############################################################################
 import logging
@@ -76,7 +76,7 @@ PYTHON_VERSIONS = ["3.6.14", "3.7.13", "3.8.13", "3.9.11", "3.10.3", "3.11.0"]
 JSON_VERSION = "v3.6.1"
 OCE_VERSION = "0.18.3"
 OCCT_VERSION = "7.5.3"
-BOOST_VERSION = "1.71.0"
+BOOST_VERSION = "1.80.0"
 PCRE_VERSION = "8.41"
 LIBXML2_VERSION = "2.9.11"
 SWIG_VERSION = "4.0.2"
@@ -103,6 +103,9 @@ curl = "curl"
 wget = "wget"
 strip = "strip"
 
+explicit_targets = [s for s in sys.argv[1:] if not s.startswith("-")]
+flags = set(s.lstrip('-') for s in sys.argv[1:] if s.startswith("-"))
+
 # Helper function for coloured printing
 
 NO_COLOR = "\033[0m" # <ref>http://stackoverflow.com/questions/5947742/how-to-change-the-output-color-of-echo-in-linux</ref>
@@ -135,9 +138,11 @@ if platform.system() == "Darwin":
 
 IFCOS_NUM_BUILD_PROCS = os.getenv("IFCOS_NUM_BUILD_PROCS", multiprocessing.cpu_count() + 1)
 
-CMAKE_DIR = os.path.realpath(os.path.join("..", "cmake"))
+CMAKE_DIR = os.path.realpath(os.path.join(os.path.dirname(__file__), "..", "cmake"))
 
-path = ["..", "build", platform.system(), platform.machine()]
+build_dir = os.environ.get("BUILD_DIR", os.path.join(os.path.dirname(__file__), "..", "build"))
+
+path = [build_dir, platform.system(), "wasm" if "wasm" in flags else platform.machine()]
 if TOOLSET:
     path.append(TOOLSET)
 DEFAULT_DEPS_DIR = os.path.realpath(os.path.join(*path))
@@ -186,11 +191,12 @@ dependency_tree = {
     'boost': (),
     'libxml2': (),
     'python': (),
-    'occ': (),
+    'occ': ('freetype',),
     'pcre': (),
     'json': (),
     'hdf5': (),
-    'cgal': ()
+    'cgal': (),
+    'freetype': (),
 }
 
 def v(dep):
@@ -199,10 +205,12 @@ def v(dep):
      for x in v(d):
        yield x
 
-tgts = [s for s in sys.argv[1:] if not s.startswith("-")]
+if "v" in flags:
-flags = set(s for s in sys.argv[1:] if s.startswith("-"))
+    logger.setLevel(logging.DEBUG)
+else:
+    logger.setLevel(logging.INFO)
 
-BUILD_STATIC = not "-shared" in flags
+BUILD_STATIC = "shared" not in flags
 ENABLE_FLAG = "--enable-static" if BUILD_STATIC else "--enable-shared"
 DISABLE_FLAG = "--disable-shared" if BUILD_STATIC else "--disable-static"
 LINK_TYPE = "static" if BUILD_STATIC else "shared"
@@ -210,10 +218,15 @@ LINK_TYPE_UCFIRST = LINK_TYPE[0].upper() + LINK_TYPE[1:]
 LIBRARY_EXT = "a" if BUILD_STATIC else "so"
 PIC = "-fPIC" if BUILD_STATIC else ""
 
-if len(tgts):
+if any(f.startswith("py-") for f in flags):
-    targets = set(sum((list(v(target)) for target in tgts), []))
+    PYTHON_VERSIONS = [pyv for pyv in PYTHON_VERSIONS if "py-%s" % "".join(pyv.split('.')[0:2]) in flags]
+
+if len(explicit_targets):
+    targets = set(sum((list(v(target)) for target in explicit_targets), []))
 else:
     targets = set(dependency_tree.keys())
+    
+targets = set(t for t in targets if 'without-%s' % t.lower() not in flags)
 
 print("Building:", *sorted(targets, key=lambda t: len(list(v(t)))))
 
@@ -237,7 +250,7 @@ if not os.path.exists(LOG_FILE):
     open(LOG_FILE, "w").close()
 logger.info(f"using command log file '{LOG_FILE}'")
 
-def run(cmds, cwd=None):
+def run(cmds, cwd=None, can_fail=False):
 
     """
     Wraps `subprocess.Popen.communicate()` and logs the command being executed,
@@ -254,7 +267,7 @@ def run(cmds, cwd=None):
     log_file_handle.close()
     logger.debug(f"command returned {proc.returncode}")
 
-    if proc.returncode != 0:
+    if proc.returncode != 0 and not can_fail:
         print("-" * 70)
         print(stderr)
         print("-" * 70)
@@ -284,7 +297,12 @@ def run_autoconf(arg1, configure_args, cwd):
         run([bash, "./autogen.sh"], cwd=os.path.realpath(os.path.join(cwd, ".."))) # only run autogen.sh in the directory it is located and use cwd to achieve that in order to not mess up things
     # Using `sh` over `bash` fixes issues with building swig 
     prefix = os.path.realpath(f"{DEPS_DIR}/install/{arg1}")
-    run(["/bin/sh", "../configure"] + configure_args + [f"--prefix={prefix}"], cwd=cwd)
+
+    wasm = []
+    if "wasm" in flags:
+        wasm.append("emconfigure")
+
+    run([*wasm, "/bin/sh", "../configure"] + configure_args + [f"--prefix={prefix}"], cwd=cwd)
 
 
 def run_cmake(arg1, cmake_args, cmake_dir=None, cwd=None):
@@ -292,7 +310,12 @@ def run_cmake(arg1, cmake_args, cmake_dir=None, cwd=None):
         P = ".."
     else:
         P = cmake_dir
-    run(["cmake", P] + cmake_args + [f"-DCMAKE_BUILD_TYPE={BUILD_CFG}"], cwd=cwd)
+        
+    wasm = []
+    if "wasm" in flags:
+        wasm.append("emcmake")
+        
+    run([*wasm, "cmake", P, *cmake_args, f"-DCMAKE_BUILD_TYPE={BUILD_CFG}"], cwd=cwd)
 
 
 def git_clone_or_pull_repository(clone_url, target_dir, revision=None):
@@ -374,12 +397,15 @@ def build_dependency(name, mode, build_tool_args, download_url, download_name, d
             urlretrieve(url, os.path.join(extract_dir, path))
             
     if patch is not None:
-        patch_abs = os.path.abspath(os.path.join(os.path.dirname(__file__), patch))
+        if isinstance(patch, str):
-        if os.path.exists(patch_abs):
+            patch = [patch]
-            try: run(["patch", "-p1", "--batch", "--forward", "-i", patch_abs], cwd=extract_dir)
+        for p in patch:
-            except Exception as e:
+            patch_abs = os.path.abspath(os.path.join(os.path.dirname(__file__), p))
-                # Assert that the patch has already been applied
+            if os.path.exists(patch_abs):
-                run(["patch", "-p1", "--batch", "--reverse", "--dry-run", "-i", patch_abs], cwd=extract_dir)
+                try: run(["patch", "-p1", "--batch", "--forward", "-i", patch_abs], cwd=extract_dir)
+                except Exception as e:
+                    # Assert that the patch has already been applied
+                    run(["patch", "-p1", "--batch", "--reverse", "--dry-run", "-i", patch_abs], cwd=extract_dir)
     
     if mode == "ctest":
         run(["ctest", "-S", "HDF5config.cmake,BUILD_GENERATOR=Unix", "-C", BUILD_CFG, "-V", "-O", "hdf5.log"], cwd=extract_dir)
@@ -410,7 +436,7 @@ def build_dependency(name, mode, build_tool_args, download_url, download_name, d
         logger.info(f"\rConfiguring {name}...")
         run([bash, "./bootstrap.sh"], cwd=extract_dir)
         logger.info(f"\rBuilding {name}...   ")
-        run(["./b2", f"-j{IFCOS_NUM_BUILD_PROCS}"] + build_tool_args, cwd=extract_dir)
+        run(["./b2", f"-j{IFCOS_NUM_BUILD_PROCS}"] + build_tool_args, cwd=extract_dir, can_fail="wasm" in flags)
         logger.info(f"\rInstalling {name}... ")
         shutil.copytree(os.path.join(extract_dir, "boost"), os.path.join(DEPS_DIR, "install", f"boost-{BOOST_VERSION}", "boost"))
         logger.info(f"\rInstalled {name}     \n")
@@ -421,11 +447,13 @@ cecho("Collecting dependencies:", GREEN)
 # TODO: This is untested
 
 ADDITIONAL_ARGS = []
-BOOST_ADDRESS_MODEL = []
 
 if platform.system() == "Darwin":
     ADDITIONAL_ARGS = [f"-mmacosx-version-min={TOOLSET}"] + ADDITIONAL_ARGS
 
+if "wasm" in flags:
+    ADDITIONAL_ARGS.extend(("-sWASM_BIGINT", "-fexceptions"))
+
 # If the linker supports GC sections, set it up to reduce binary file size
 # -fPIC is required for the shared libraries to work
 
@@ -434,7 +462,7 @@ CFLAGS = os.environ.get("CFLAGS", "")
 LDFLAGS = os.environ.get("LDFLAGS", "")
 
 ADDITIONAL_ARGS_STR = " ".join(ADDITIONAL_ARGS)
-if sp.call([bash, "-c", "ld --gc-sections 2>&1 | grep -- --gc-sections &> /dev/null"]) != 0:
+if "wasm" not in flags and sp.call([bash, "-c", "ld --gc-sections 2>&1 | grep -- --gc-sections &> /dev/null"]) != 0:
     CXXFLAGS_MINIMAL = f"{CXXFLAGS} {PIC} {ADDITIONAL_ARGS_STR}"
     CFLAGS_MINIMAL = f"{CFLAGS} {PIC} {ADDITIONAL_ARGS_STR}"
     if BUILD_STATIC:
@@ -504,8 +532,27 @@ if "swig" in targets:
         download_tool=download_tool_git,
         revision=f"rel-{SWIG_VERSION}"
     )
+    
+if "freetype" in targets:
+    build_dependency(
+        name=f"freetype",
+        mode="cmake",
+        build_tool_args=[
+            f"-DCMAKE_INSTALL_PREFIX={DEPS_DIR}/install/freetype"
+        ],
+        download_url = "https://github.com/freetype/freetype",
+        download_name = "freetype2",
+        download_tool=download_tool_git,
+    )
 
 if USE_OCCT and "occ" in targets:
+    patches = []
+    if OCCT_VERSION < "7.4":
+        patches.append("./patches/occt/enable-exception-handling.patch")
+    
+    if "wasm" in flags:
+        patches.append("./patches/occt/no_em_js.patch")
+
     build_dependency(
         name=f"occt-{OCCT_VERSION}",
         mode="cmake",
@@ -513,12 +560,13 @@ if USE_OCCT and "occ" in targets:
             f"-DINSTALL_DIR={DEPS_DIR}/install/occt-{OCCT_VERSION}",
             f"-DBUILD_LIBRARY_TYPE={LINK_TYPE_UCFIRST}",
             "-DBUILD_MODULE_Draw=0",
-            "-DBUILD_RELEASE_DISABLE_EXCEPTIONS=Off"
+            "-DBUILD_RELEASE_DISABLE_EXCEPTIONS=Off",
+            f"-D3RDPARTY_FREETYPE_DIR={DEPS_DIR}/install/freetype"
         ],
         download_url = "https://github.com/Open-Cascade-SAS/OCCT",
         download_name = "occt",
         download_tool=download_tool_git,
-        patch=None if OCCT_VERSION >= "7.4" else "./patches/occt/enable-exception-handling.patch",
+        patch=patches,
         revision="V" + OCCT_VERSION.replace('.', '_')
     )
 elif "occ" in targets:
@@ -569,11 +617,11 @@ if "OpenCOLLADA" in targets:
         download_url="https://github.com/KhronosGroup/OpenCOLLADA.git",
         download_name="OpenCOLLADA",
         download_tool=download_tool_git,
-        patch="./patches/opencollada/pr622_and_disable_subdirs.patch",
+        patch=("./patches/opencollada/pr622_and_disable_subdirs.patch", "./patches/opencollada/remove_tr1.patch"),
         revision=OPENCOLLADA_VERSION
     )
 
-if "python" in targets and not USE_CURRENT_PYTHON_VERSION:
+if "python" in targets and not USE_CURRENT_PYTHON_VERSION and "wasm" not in flags:
     # Python should not be built with -fvisibility=hidden, from experience that introduces segfaults
     OLD_CXX_FLAGS = os.environ["CXXFLAGS"]
     OLD_C_FLAGS = os.environ["CFLAGS"]
@@ -612,6 +660,9 @@ if "python" in targets and not USE_CURRENT_PYTHON_VERSION:
 
 if "boost" in targets:
     str_concat = lambda prefix: lambda postfix: "" if postfix.strip() == "" else "=".join((prefix, postfix.strip()))
+    toolset = []
+    if "wasm" in flags:
+        toolset.append("toolset=emscripten")
     build_dependency(
         f"boost-{BOOST_VERSION}",
         mode="bjam",
@@ -623,21 +674,30 @@ if "boost" in targets:
             "--with-thread",
             "--with-date_time",
             "--with-iostreams",
-            f"link={LINK_TYPE}"
+            f"link={LINK_TYPE}",
-                                                                         ] + \
+            *toolset,
-            BOOST_ADDRESS_MODEL                                            + \
+            *map(str_concat("cxxflags"), CXXFLAGS.strip().split(' ')),
-            list(map(str_concat("cxxflags"), CXXFLAGS.strip().split(' '))) + \
+            *map(str_concat("linkflags"), LDFLAGS.strip().split(' ')),
-            list(map(str_concat("linkflags"), LDFLAGS.strip().split(' '))) + \
+            "stage", "-s", "NO_BZIP2=1"],
-            ["stage", "-s", "NO_BZIP2=1"],
         download_url=BOOST_LOCATION,
+        patch="./patches/boost/boostorg_regex_62.patch",
         download_name=f"boost_{BOOST_VERSION_UNDERSCORE}.tar.bz2"
     )
+    if "wasm" in flags:
+        # only supported on nix for now
+        run(("find", ".", "-name", "*.bc", "-exec", "bash", "-c", "emar q ${1%.bc}.a $1", "bash", "{}", ";"), cwd=f"{DEPS_DIR}/install/boost-{BOOST_VERSION}/lib")
     
 if "cgal" in targets:
+    gmp_args = []
+    mpfr_args = []
+    if "wasm" in flags:
+        gmp_args.extend(("--disable-assembly", "--host", "none", "--enable-cxx"))
+        mpfr_args.extend(("--host", "none"))
+
     build_dependency(
         name=f"gmp-{GMP_VERSION}",
         mode="autoconf",
-        build_tool_args=[ENABLE_FLAG, DISABLE_FLAG, "--with-pic"],
+        build_tool_args=[ENABLE_FLAG, DISABLE_FLAG, "--with-pic", *gmp_args],
         download_url="https://ftp.gnu.org/gnu/gmp/",
         download_name=f"gmp-{GMP_VERSION}.tar.bz2"
     )
@@ -645,7 +705,7 @@ if "cgal" in targets:
     build_dependency(
         name=f"mpfr-{MPFR_VERSION}",
         mode="autoconf",
-        build_tool_args=[ENABLE_FLAG, DISABLE_FLAG, f"--with-gmp={DEPS_DIR}/install/gmp-{GMP_VERSION}"],
+        build_tool_args=[ENABLE_FLAG, DISABLE_FLAG, *mpfr_args, f"--with-gmp={DEPS_DIR}/install/gmp-{GMP_VERSION}"],
         download_url=f"http://www.mpfr.org/mpfr-{MPFR_VERSION}/",
         download_name=f"mpfr-{MPFR_VERSION}.tar.bz2"
     )
@@ -679,18 +739,8 @@ os.makedirs(IFCOS_DIR, exist_ok=True)
 executables_dir = os.path.join(IFCOS_DIR, "executables")
 os.makedirs(executables_dir, exist_ok=True)
 
-logger.info("\rConfiguring executables...")
-
 OFF_ON = ["OFF", "ON"]
 
-exec_args = [
-    "-DBUILD_IFCGEOM="                 +OFF_ON["IfcGeom" in targets],
-    "-DBUILD_GEOMSERVER="              +OFF_ON["IfcGeomServer" in targets],
-    "-DBUILD_CONVERT="                 +OFF_ON["IfcConvert" in targets],
-    "-DBUILD_IFCPYTHON="               "OFF",
-    "-DCMAKE_INSTALL_PREFIX="          f"{DEPS_DIR}/install/ifcopenshell",
-]
-
 cmake_args = [
     "-DUSE_MMAP="                      "OFF",
     "-DBUILD_EXAMPLES="                "OFF",
@@ -702,6 +752,11 @@ cmake_args = [
     "-DADD_COMMIT_SHA="              +("On" if ADD_COMMIT_SHA else "Off")
 ]
 
+if "wasm" in flags:
+    # Boost is built by the build script so should not be found
+    # inside of the sysroot set by the emscriptem toolchain
+    cmake_args.append("-DWASM_BUILD=On")
+
 if "cgal" in targets:
     cmake_args.extend([
         "-DCGAL_INCLUDE_DIR="          f"{DEPS_DIR}/install/cgal-{CGAL_VERSION}/include",
@@ -753,20 +808,36 @@ if "hdf5" in targets:
         "-DHDF5_INCLUDE_DIR="          f"{DEPS_DIR}/install/hdf5-{HDF5_VERSION}/include",
         "-DHDF5_LIBRARY_DIR="          f"{DEPS_DIR}/install/hdf5-{HDF5_VERSION}/lib"
     ])
+else:
+    cmake_args.append("-DHDF5_SUPPORT=Off")
 
-run_cmake("", exec_args + cmake_args, cmake_dir=CMAKE_DIR, cwd=executables_dir)
+if not explicit_targets or {"IfcGeom", "IfcConvert", "IfcGeomServer"} & set(explicit_targets):
+    logger.info("\rConfiguring executables...")
 
-logger.info("\rBuilding executables...   ")
+    exec_args = [
+        "-DBUILD_IFCGEOM="                 +OFF_ON["IfcGeom" in targets],
+        "-DBUILD_GEOMSERVER="              +OFF_ON["IfcGeomServer" in targets],
+        "-DBUILD_CONVERT="                 +OFF_ON["IfcConvert" in targets],
+        "-DBUILD_IFCPYTHON="               "OFF",
+        "-DCMAKE_INSTALL_PREFIX="          f"{DEPS_DIR}/install/ifcopenshell",
+    ]
+    
+    run_cmake("", exec_args + cmake_args, cmake_dir=CMAKE_DIR, cwd=executables_dir)
 
-run([make, f"-j{IFCOS_NUM_BUILD_PROCS}"], cwd=executables_dir)
+    logger.info("\rBuilding executables...   ")
-run([make, "install/strip" if BUILD_CFG == "Release" else "install"], cwd=executables_dir)
+
+    run([make, f"-j{IFCOS_NUM_BUILD_PROCS}"], cwd=executables_dir)
+    run([make, "install/strip" if BUILD_CFG == "Release" else "install"], cwd=executables_dir)
 
 if "IfcOpenShell-Python" in targets:
     # On OSX the actual Python library is not linked against.
     ADDITIONAL_ARGS = ""
     if platform.system() == "Darwin":
         ADDITIONAL_ARGS = "-Wl,-flat_namespace,-undefined,suppress"
-
+        
+    if "wasm" in flags:
+        ADDITIONAL_ARGS = f"-Wl,-undefined,suppress -sSIDE_MODULE=2 -sEXPORTED_FUNCTIONS=_PyInit__ifcopenshell_wrapper"
+        
     os.environ["CXXFLAGS"] = f"{CXXFLAGS_MINIMAL} {ADDITIONAL_ARGS}"
     os.environ["CFLAGS"] = f"{CFLAGS_MINIMAL} {ADDITIONAL_ARGS}"
     os.environ["LDFLAGS"] = f"{LDFLAGS} {ADDITIONAL_ARGS}"
@@ -783,36 +854,57 @@ if "IfcOpenShell-Python" in targets:
 
         os.environ["PYTHON_LIBRARY_BASENAME"] = os.path.basename(python_library)
 
+        swig_when_built = []
+        if "swig" in targets:
+            swig_when_built.append(f"-DSWIG_EXECUTABLE={DEPS_DIR}/install/swig/bin/swig")
+
         run_cmake("",
             cmake_args + [
                 "-DPYTHON_LIBRARY="          +python_library,
-                "-DPYTHON_EXECUTABLE="       +python_executable,
+                *([f"-DPYTHON_EXECUTABLE={python_executable}"] if python_executable else []),
+                # *([f"-DPYTHON_MODULE_INSTALL_DIR={os.environ['PYTHONPATH']}/ifcopenshell"] if "wasm" in flags else []),
+                *(["-DPYTHON_MODULE_INSTALL_DIR="+os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "package"))] if "wasm" in flags else []),
                 "-DPYTHON_INCLUDE_DIR="      +python_include,
-                "-DSWIG_EXECUTABLE="         f"{DEPS_DIR}/install/swig/bin/swig",
                 "-DCMAKE_INSTALL_PREFIX="    f"{DEPS_DIR}/install/ifcopenshell/tmp",
-                "-DUSERSPACE_PYTHON_PREFIX=" +["Off", "On"][os.environ.get("PYTHON_USER_SITE", "").lower() in {"1", "on", "true"}]
+                "-DUSERSPACE_PYTHON_PREFIX=" +["Off", "On"][os.environ.get("PYTHON_USER_SITE", "").lower() in {"1", "on", "true"}],
-            ], cmake_dir=CMAKE_DIR, cwd=python_dir)
+                *swig_when_built],
+            cmake_dir=CMAKE_DIR, cwd=python_dir)
 
         logger.info(f"\rBuilding python {python_version} wrapper...   ")
 
         run([make, f"-j{IFCOS_NUM_BUILD_PROCS}", "_ifcopenshell_wrapper"], cwd=python_dir)
         run([make, "install/local"], cwd=os.path.join(python_dir, "ifcwrap"))
 
-        module_dir = os.path.dirname(run([python_executable, "-c", "import inspect, ifcopenshell; print(inspect.getfile(ifcopenshell))"]))
+        if python_executable:
+            module_dir = os.path.dirname(run([python_executable, "-c", "import inspect, ifcopenshell; print(inspect.getfile(ifcopenshell))"]))
 
-        if platform.system() != "Darwin":
+            if platform.system() != "Darwin":
-            # TODO: This symbol name depends on the Python version?
+                # TODO: This symbol name depends on the Python version?
-            run([strip, "-s", "-K", "PyInit__ifcopenshell_wrapper", "_ifcopenshell_wrapper.so"], cwd=module_dir)
+                run([strip, "-s", "-K", "PyInit__ifcopenshell_wrapper", "_ifcopenshell_wrapper.so"], cwd=module_dir)
-        return module_dir
 
+            return module_dir
 
-    if USE_CURRENT_PYTHON_VERSION:
+    if "wasm" in flags:
-        python_info = sysconfig.get_paths()
+        compile_python_wrapper(
-        python_lib = os.path.join(
+            f"{os.environ['PYMAJOR']}.{os.environ['PYMINOR']}.{os.environ['PYMICRO']}",
-            sysconfig.get_config_var('LIBDIR'), 
+            f"{os.environ['TARGETINSTALLDIR']}/lib/libpython{os.environ['PYMAJOR']}.{os.environ['PYMINOR']}.a",
-            sysconfig.get_config_var('multiarchsubdir').replace("/", ""), 
+            os.environ['PYTHONINCLUDE'],
-            sysconfig.get_config_var("INSTSONAME")
+            None
         )
+    
+    elif USE_CURRENT_PYTHON_VERSION:
+        python_info = sysconfig.get_paths()
+
+        py_path_components = [
+            sysconfig.get_config_var('LIBDIR'),
+            sysconfig.get_config_var("INSTSONAME")
+        ]
+
+        if sysconfig.get_config_var('multiarchsubdir'):
+            py_path_components.insert(1, sysconfig.get_config_var('multiarchsubdir').replace("/", ""))
+
+        python_lib = os.path.join(*py_path_components)
+
         compile_python_wrapper(platform.python_version(), python_lib, python_info["include"], sys.executable)
     else:
         for python_version in PYTHON_VERSIONS:

nix/patches/boost/boostorg_regex_62.patch

@@ -0,0 +1,20 @@
+--- a/tools/build/src/tools/emscripten.jam
++++ b/tools/build/src/tools/emscripten.jam
+@@ -6,6 +6,7 @@
+ import feature ;
+ import os ;
+ import toolset ;
++import generators ;
+ import common ;
+ import gcc ;
+ import type ;
+@@ -52,6 +53,8 @@
+         <debug-symbols>off <debug-symbols>on
+         <rtti>off <rtti>on
+         ;
++generators.override builtin.lib-generator : emscripten.prebuilt ;
++generators.override emscripten.searched-lib-generator : searched-lib-generator ;
+ 
+ type.set-generated-target-suffix EXE : <toolset>emscripten : "js" ;
+ type.set-generated-target-suffix OBJ : <toolset>emscripten : "bc" ;
+ 

nix/patches/occt/no_em_js.patch

@@ -0,0 +1,99 @@
+diff --git a/src/Message/Message_PrinterSystemLog.cxx b/src/Message/Message_PrinterSystemLog.cxx
+index 0c82c2167..a2e9e6d68 100644
+--- a/src/Message/Message_PrinterSystemLog.cxx
++++ b/src/Message/Message_PrinterSystemLog.cxx
+@@ -55,27 +55,6 @@
+     return ANDROID_LOG_DEBUG;
+   }
+ #elif defined(__EMSCRIPTEN__)
+-  #include <emscripten/emscripten.h>
+-
+-  //! Print message to console.debug().
+-  EM_JS(void, occJSConsoleDebug, (const char* theStr), {
+-    console.debug(UTF8ToString(theStr));
+-  });
+-
+-  //! Print message to console.info().
+-  EM_JS(void, occJSConsoleInfo, (const char* theStr), {
+-    console.info(UTF8ToString(theStr));
+-  });
+-
+-  //! Print message to console.warn().
+-  EM_JS(void, occJSConsoleWarn, (const char* theStr), {
+-    console.warn(UTF8ToString(theStr));
+-  });
+-
+-  //! Print message to console.error().
+-  EM_JS(void, occJSConsoleError, (const char* theStr), {
+-    console.error(UTF8ToString(theStr));
+-  });
+ #else
+   #include <syslog.h>
+ 
+@@ -169,16 +148,6 @@ void Message_PrinterSystemLog::send (const TCollection_AsciiString& theString,
+ #elif defined(__ANDROID__)
+   __android_log_write (getAndroidLogPriority (theGravity), myEventSourceName.ToCString(), theString.ToCString());
+ #elif defined(__EMSCRIPTEN__)
+-  // don't use bogus emscripten_log() corrupting UNICODE strings
+-  switch (theGravity)
+-  {
+-    case Message_Trace:   occJSConsoleDebug(theString.ToCString()); return;
+-    case Message_Info:    occJSConsoleInfo (theString.ToCString()); return;
+-    case Message_Warning: occJSConsoleWarn (theString.ToCString()); return;
+-    case Message_Alarm:   occJSConsoleError(theString.ToCString()); return;
+-    case Message_Fail:    occJSConsoleError(theString.ToCString()); return;
+-  }
+-  occJSConsoleWarn (theString.ToCString());
+ #else
+   syslog (getSysLogPriority (theGravity), "%s", theString.ToCString());
+ #endif
+diff --git a/src/OSD/OSD_MemInfo.cxx b/src/OSD/OSD_MemInfo.cxx
+index 08a939beb..7c1fc79b3 100644
+--- a/src/OSD/OSD_MemInfo.cxx
++++ b/src/OSD/OSD_MemInfo.cxx
+@@ -37,15 +37,6 @@
+ 
+ #include <OSD_MemInfo.hxx>
+ 
+-#if defined(__EMSCRIPTEN__)
+-  #include <emscripten.h>
+-
+-  //! Return WebAssembly heap size in bytes.
+-  EM_JS(size_t, OSD_MemInfo_getModuleHeapLength, (), {
+-    return Module.HEAP8.length;
+-  });
+-#endif
+-
+ // =======================================================================
+ // function : OSD_MemInfo
+ // purpose  :
+@@ -156,29 +147,6 @@ void OSD_MemInfo::Update()
+   }
+ 
+ #elif defined(__EMSCRIPTEN__)
+-  if (IsActive (MemHeapUsage)
+-   || IsActive (MemWorkingSet)
+-   || IsActive (MemWorkingSetPeak))
+-  {
+-    // /proc/%d/status is not emulated - get more info from mallinfo()
+-    const struct mallinfo aMI = mallinfo();
+-    if (IsActive (MemHeapUsage))
+-    {
+-      myCounters[MemHeapUsage] = aMI.uordblks;
+-    }
+-    if (IsActive (MemWorkingSet))
+-    {
+-      myCounters[MemWorkingSet] = aMI.uordblks;
+-    }
+-    if (IsActive (MemWorkingSetPeak))
+-    {
+-      myCounters[MemWorkingSetPeak] = aMI.usmblks;
+-    }
+-  }
+-  if (IsActive (MemVirtual))
+-  {
+-    myCounters[MemVirtual] = OSD_MemInfo_getModuleHeapLength();
+-  }
+ #elif (defined(__linux__) || defined(__linux))
+   if (IsActive (MemHeapUsage))
+   {

nix/patches/opencollada/remove_tr1.patch

@@ -0,0 +1,81 @@
+diff --git a/COLLADABaseUtils/include/COLLADABUhash_map.h b/COLLADABaseUtils/include/COLLADABUhash_map.h
+index 8ab0fb9b..12503bfb 100644
+--- a/COLLADABaseUtils/include/COLLADABUhash_map.h
++++ b/COLLADABaseUtils/include/COLLADABUhash_map.h
+@@ -32,9 +32,9 @@
+             #include <unordered_map>
+             #include <unordered_set>
+ 
+-            #define COLLADABU_HASH_MAP std::tr1::unordered_map
+-			#define COLLADABU_HASH_MULTIMAP std::tr1::unordered_multimap
+-            #define COLLADABU_HASH_SET std::tr1::unordered_set
++            #define COLLADABU_HASH_MAP std::unordered_map
++			#define COLLADABU_HASH_MULTIMAP std::unordered_multimap
++            #define COLLADABU_HASH_SET std::unordered_set
+             #define COLLADABU_HASH_NAMESPACE_OPEN std { namespace tr1
+             #define COLLADABU_HASH_NAMESPACE_CLOSE }
+             #define COLLADABU_HASH_FUN hash
+@@ -50,12 +50,12 @@
+             #define COLLADABU_HASH_FUN hash
+         #endif
+     #elif defined(__MINGW32__) || defined(__MINGW64__)
+-        #include <tr1/unordered_map>
+-        #include <tr1/unordered_set>
++        #include <unordered_map>
++        #include <unordered_set>
+ 
+-        #define COLLADABU_HASH_MAP std::tr1::unordered_map
+-        #define COLLADABU_HASH_MULTIMAP std::tr1::unordered_multimap
+-        #define COLLADABU_HASH_SET std::tr1::unordered_set
++        #define COLLADABU_HASH_MAP std::unordered_map
++        #define COLLADABU_HASH_MULTIMAP std::unordered_multimap
++        #define COLLADABU_HASH_SET std::unordered_set
+         #define COLLADABU_HASH_NAMESPACE_OPEN std { namespace tr1
+         #define COLLADABU_HASH_NAMESPACE_CLOSE }
+         #define COLLADABU_HASH_FUN hash
+@@ -107,12 +107,12 @@
+         #define COLLADABU_HASH_NAMESPACE_CLOSE
+         #define COLLADABU_HASH_FUN hash
+     #else
+-        #include <tr1/unordered_map>
+-        #include <tr1/unordered_set>
++        #include <unordered_map>
++        #include <unordered_set>
+ 
+-		#define COLLADABU_HASH_MAP std::tr1::unordered_map
+-		#define COLLADABU_HASH_MULTIMAP std::tr1::unordered_multimap
+-        #define COLLADABU_HASH_SET std::tr1::unordered_set
++		#define COLLADABU_HASH_MAP std::unordered_map
++		#define COLLADABU_HASH_MULTIMAP std::unordered_multimap
++        #define COLLADABU_HASH_SET std::unordered_set
+         #define COLLADABU_HASH_NAMESPACE_OPEN std { namespace tr1
+         #define COLLADABU_HASH_NAMESPACE_CLOSE }
+         #define COLLADABU_HASH_FUN hash
+diff --git a/common/libBuffer/include/CommonFWriteBufferFlusher.h b/common/libBuffer/include/CommonFWriteBufferFlusher.h
+index c7af45b2..fac4f133 100644
+--- a/common/libBuffer/include/CommonFWriteBufferFlusher.h
++++ b/common/libBuffer/include/CommonFWriteBufferFlusher.h
+@@ -15,12 +15,12 @@
+ 
+ #if (defined(WIN64) || defined(_WIN64) || defined(__WIN64__)) || (defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__) || defined(__APPLE__))
+ #if defined(__GNUC__) && !defined(_LIBCPP_VERSION)
+-#	include <tr1/unordered_map>
++#	include <unordered_map>
+ #else
+ #	include <unordered_map>
+ #endif
+ #else
+-#	include <tr1/unordered_map>
++#	include <unordered_map>
+ #endif
+ 
+ #ifdef _LIBCPP_VERSION
+@@ -58,7 +58,7 @@ namespace Common
+ #else
+ 		typedef __int64 FilePosType;
+ #endif
+-	typedef std::tr1::unordered_map<MarkId, FilePosType > MarkIdToFilePos;
++	typedef std::unordered_map<MarkId, FilePosType > MarkIdToFilePos;
+ 
+ 	public:
+ 		static const size_t DEFAUL_BUFFER_SIZE = 64*1024;

pyodide/meta.yaml

@@ -0,0 +1,18 @@
+package:
+  name: ifcopenshell
+  version: 0.7.0
+
+source:
+  path: IfcOpenShell
+
+build:
+  script: |
+    python nix/build-all.py --without-hdf5 --without-opencollada --without-swig --without-pcre -v --wasm --py310 IfcOpenShell-Python
+    cp pyodide/setup.py .
+
+about:
+  home: http://ifcopenshell.org
+  license: LGPL-3.0-or-later
+  summary: |
+    IfcOpenShell is an open source (LGPL) software library for 
+    working with the Industry Foundation Classes (IFC) file format.

pyodide/setup.py

@@ -0,0 +1,11 @@
+from setuptools import setup, find_packages
+
+setup(name='IfcOpenShell',
+      version='0.7.0',
+      description='IfcOpenShell is an open source (LGPL) software library for working with the Industry Foundation Classes (IFC) file format.',
+      author='Thomas Krijnen',
+      author_email='thomas@aecgeeks.com',
+      url='http://ifcopenshell.org',
+      packages=find_packages(),
+      package_data={'': ['*.so']},
+)

src/ifcwrap/CMakeLists.txt

@@ -67,20 +67,24 @@ endif()
 # Try to find the Python interpreter to get the site-packages
 # directory in which the wrapper can be installed.
 FIND_PACKAGE(PythonInterp)
-IF(PYTHONINTERP_FOUND AND NOT "${PYTHON_EXECUTABLE}" STREQUAL "")
+IF((PYTHONINTERP_FOUND AND NOT "${PYTHON_EXECUTABLE}" STREQUAL "") OR PYTHON_MODULE_INSTALL_DIR)
-    IF (USERSPACE_PYTHON_PREFIX)
+    if (PYTHON_MODULE_INSTALL_DIR)
-        EXECUTE_PROCESS(
+	set(python_package_dir "${PYTHON_MODULE_INSTALL_DIR}")
-            COMMAND ${PYTHON_EXECUTABLE} -c "import sys; import site; sys.stdout.write(site.USER_SITE)"
+    else()
-            OUTPUT_VARIABLE python_package_dir
+        IF (USERSPACE_PYTHON_PREFIX)
-        )
+            EXECUTE_PROCESS(
-    ELSE ()
+                COMMAND ${PYTHON_EXECUTABLE} -c "import sys; import site; sys.stdout.write(site.USER_SITE)"
-        EXECUTE_PROCESS(
+                OUTPUT_VARIABLE python_package_dir
-            COMMAND ${PYTHON_EXECUTABLE} -c "import sys; from distutils.sysconfig import get_python_lib; sys.stdout.write(get_python_lib(1))"
+            )
-            OUTPUT_VARIABLE python_package_dir
+        ELSE ()
-        )
+            EXECUTE_PROCESS(
-    ENDIF()
+                COMMAND ${PYTHON_EXECUTABLE} -c "import sys; from distutils.sysconfig import get_python_lib; sys.stdout.write(get_python_lib(1))"
-    if (BUILD_PACKAGE)
+                OUTPUT_VARIABLE python_package_dir
-        set(python_package_dir ${CMAKE_INSTALL_LIBDIR}/python${PYTHON_VERSION_MAJOR}/dist-packages/)
+            )
+        ENDIF()
+        if (BUILD_PACKAGE)
+            set(python_package_dir ${CMAKE_INSTALL_LIBDIR}/python${PYTHON_VERSION_MAJOR}/dist-packages/)
+        endif()
     endif()
     IF("${python_package_dir}" STREQUAL "")
         MESSAGE(WARNING "Unable to locate Python site-package directory, unable to install the Python wrapper")