Merge pull request #27 from Birch-san/update-build-rebased

Build with newer Emscripten and different flags

Author: Birch-san

box2d-wasm/README.dev.md

@@ -2,7 +2,7 @@
 
 Ensure that you have a recent [emscripten](https://emscripten.org/) installed.
 
-This build process is known to work with emscripten 2.0.5.
+**Requires Emscripten 2.0.16 or higher.**
 
 ### Overview
 
@@ -12,8 +12,6 @@ Navigate to `<repository root>/box2d-wasm`, then:
 export TARGET_TYPE=Debug
 export EMSCRIPTEN="${EMSCRIPTEN:-"$(realpath "$(dirname $(realpath "$(which emcc)"))/../libexec")"}"
 export PYTHON="${PYTHON:-"$(which python3)"}"
-# if you're developing in this monorepo, you'll be testing your changes with integration-test, which doesn't use the UMD output
-export SKIP_UMD_BUILD=1
 ./build_all.sh
 ```
 

box2d-wasm/build_makefile.sh

@@ -13,30 +13,9 @@ fi
 
 >&2 echo -e '\nGenerating Makefile with emcmake'
 
-# if we were to pass -DCMAKE_BUILD_TYPE="$TARGET_TYPE" to emcmake,
-# emcmake would enforce the following overrides (see build/CMakeCache.txt after running emcmake)
-#   CMAKE_CXX_FLAGS_DEBUG:STRING=-g
-#   CMAKE_CXX_FLAGS_MINSIZEREL:STRING=-DNDEBUG -Os
-#   CMAKE_CXX_FLAGS_RELEASE:STRING=-DNDEBUG -O2
-#   CMAKE_CXX_FLAGS_RELWITHDEBINFO:STRING=-DNDEBUG -O2
-# these flags would be applied *after* ours, which means they would have precedence.
-# as such: we do *not* set CMAKE_BUILD_TYPE, because we wish for higher optimization (O3) on Release builds
-# see how the flags get resolved in build/src/CMakeFiles/box2d.dir/flags.make
-CMAKE_CXX_FLAGS=()
-RELEASE_FLAGS_NOMINAL=(-DNDEBUG -O3)
-
 case "$TARGET_TYPE" in
-  RelWithDebInfo)
-    # -flto can succeed here, but causes the emcc after this to fail during wasm-emscripten-finalize (possibly due to source maps)
-    CMAKE_CXX_FLAGS=(${RELEASE_FLAGS_NOMINAL[@]} -g)
-    ;;
-  Release)
-    CMAKE_CXX_FLAGS=(${RELEASE_FLAGS_NOMINAL[@]} -flto)
+  RelWithDebInfo | Release | Debug)
     ;;
-  Debug)
-    CMAKE_CXX_FLAGS=(-g)
-    ;;
-
   *)
     >&2 echo -e "${Red}TARGET_TYPE not set.${NC}"
     >&2 echo -e "Please set TARGET_TYPE to 'Debug', 'Release', or 'RelWithDebInfo'. For example, with:"
@@ -47,4 +26,4 @@ esac
 >&2 echo -e "TARGET_TYPE is $TARGET_TYPE"
 
 set -x
-emcmake cmake -DCMAKE_CXX_FLAGS="$CMAKE_CXX_FLAGS" ../../box2d -DBOX2D_BUILD_UNIT_TESTS=OFF -DBOX2D_BUILD_DOCS=OFF -DBOX2D_BUILD_TESTBED=OFF
+emcmake cmake -DCMAKE_BUILD_TYPE="$TARGET_TYPE" ../../box2d -DBOX2D_BUILD_UNIT_TESTS=OFF -DBOX2D_BUILD_DOCS=OFF -DBOX2D_BUILD_TESTBED=OFF

box2d-wasm/build_wasm.sh

@@ -14,23 +14,48 @@ if ! [[ "$PWD" -ef "$DIR/build" ]]; then
 fi
 
 # we used to use -s ENVIRONMENT=web for a slightly smaller build, until Node.js compatibility was requested in https://github.com/Birch-san/box2d-wasm/issues/8
-EMCC_OPTS=(-s MODULARIZE=1 -s EXPORT_NAME=Box2D -s EXPORT_BINDINGS=1 -s RESERVED_FUNCTION_POINTERS=20 --post-js box2d_glue.js --memory-init-file 0 -s NO_EXIT_RUNTIME=1 -s NO_FILESYSTEM=1 -s EXPORTED_RUNTIME_METHODS=[] -s EXPORTED_FUNCTIONS="['_malloc','_free']" -fno-rtti -s ALLOW_MEMORY_GROWTH=1)
-
-RELEASE_OPTS_NOMINAL=(-O3)
+EMCC_OPTS=(
+  -fno-rtti
+  -s MODULARIZE=1
+  -s EXPORT_NAME=Box2D
+  -s ALLOW_TABLE_GROWTH=1
+  --post-js box2d_glue.js
+  --memory-init-file 0
+  -s FILESYSTEM=0
+  -s SUPPORT_LONGJMP=0
+  -s EXPORTED_FUNCTIONS=_malloc,_free
+  -s ALLOW_MEMORY_GROWTH=1
+  )
+RELEASE_OPTS=(-O3)
 
 case "$TARGET_TYPE" in
   Debug)
-    FLAVOUR_EMCC_OPTS=(-g4 -s ASSERTIONS=2 -s DEMANGLE_SUPPORT=1)
+    EMCC_OPTS=(
+      ${EMCC_OPTS[@]}
+      -g4
+      -s ASSERTIONS=2
+      -s DEMANGLE_SUPPORT=1
+      )
     ;;
 
   RelWithDebInfo)
     # consider setting --source-map-base if you know where
     # Box2D will be served from.
-    FLAVOUR_EMCC_OPTS=(-g4 ${RELEASE_OPTS_NOMINAL[@]})
+    EMCC_OPTS=(
+      ${EMCC_OPTS[@]}
+      ${RELEASE_OPTS[@]}
+      -g4
+      )
     ;;
 
   Release)
-    FLAVOUR_EMCC_OPTS=(-flto --closure 1 -s IGNORE_CLOSURE_COMPILER_ERRORS=1 ${RELEASE_OPTS_NOMINAL[@]})
+    EMCC_OPTS=(
+      ${EMCC_OPTS[@]}
+      ${RELEASE_OPTS[@]}
+      -flto
+      --closure 1
+      -s IGNORE_CLOSURE_COMPILER_ERRORS=1
+      )
     ;;
 
   *)
@@ -42,28 +67,60 @@ case "$TARGET_TYPE" in
 esac
 >&2 echo -e "TARGET_TYPE is $TARGET_TYPE"
 
-EMCC_COMMAND_NOMINAL=("${EMCC_OPTS[@]}" "${FLAVOUR_EMCC_OPTS[@]}" -I "$DIR/../box2d/include" --post-js "$DIR/glue_stub.js" "$DIR/glue_stub.cpp" bin/libbox2d.a)
 
 BASENAME='Box2D'
+BARE_WASM="$BASENAME.bare.wasm"
+
+>&2 echo -e "${Blue}Building bare WASM${NC}"
+set -x
+emcc "$DIR/glue_stub.cpp" bin/libbox2d.a -I "$DIR/../box2d/include" "${EMCC_OPTS[@]}" --oformat=bare -o "$BARE_WASM"
+{ set +x; } 2>&-
+>&2 echo -e "${Green}Successfully built $BARE_WASM${NC}\n"
 
 UMD_DIR='umd'
 ES_DIR='es'
 mkdir -p "$UMD_DIR" "$ES_DIR"
 
-if [ "$SKIP_UMD_BUILD" = "1" ]; then
-  >&2 echo -e "${Green}Skipped UMD build because we gotta go fast${NC}"
-else
-  UMD_FILE="$UMD_DIR/$BASENAME.js"
-  >&2 echo -e "${Blue}Building UMD module, $UMD_FILE${NC}"
-  set -x
-  emcc "${EMCC_COMMAND_NOMINAL[@]}" -o "$UMD_FILE"
-  { set +x; } 2>&-
-  >&2 echo -e "${Green}Successfully built $UMD_FILE${NC}\n"
-fi
+>&2 echo -e "${Blue}Building post-link targets${NC}"
+
+LINK_OPTS=(--post-link "$BARE_WASM" --post-js "$DIR/glue_stub.js" ${EMCC_OPTS[@]})
 
 ES_FILE="$ES_DIR/$BASENAME.js"
->&2 echo -e "${Blue}Building ES module, $ES_FILE${NC}"
+>&2 echo -e "${Blue}Building ES module, $ES_DIR/$BASENAME.{js,wasm}${NC}"
 set -x
-emcc "${EMCC_COMMAND_NOMINAL[@]}" -s EXPORT_ES6=1 -o "$ES_FILE"
+emcc "${LINK_OPTS[@]}" -s EXPORT_ES6=1 -o "$ES_FILE"
 { set +x; } 2>&-
->&2 echo -e "${Green}Successfully built $ES_FILE${NC}"
+>&2 echo -e "${Green}Successfully built $ES_DIR/$BASENAME.{js,wasm}${NC}\n"
+
+UMD_FILE="$UMD_DIR/$BASENAME.js"
+if [ "$BUILD_UMD_FROM_SCRATCH" = "1" ]; then
+  >&2 echo -e "${Blue}Building UMD module, $UMD_DIR/$BASENAME.{js,wasm} from scratch${NC}"
+  set -x
+  emcc "${LINK_OPTS[@]}" -o "$UMD_FILE"
+  { set +x; } 2>&-
+else
+  >&2 echo -e "${Blue}Building UMD module, $UMD_DIR/$BASENAME.{js,wasm} by replacing header & footer of ES module${NC}"
+  escape_for_sed_replace () {
+    echo "$1" | sed -e 's/&/\\\&/g' -e '$!s/$/\\n/' | tr -d '\n'
+  }
+
+  ES6_HEADER='  var _scriptDir = import.meta.url;'
+  UMD_HEADER="  var _scriptDir = typeof document !== 'undefined' && document.currentScript ? document.currentScript.src : undefined;
+  if (typeof __filename !== 'undefined') _scriptDir = _scriptDir || __filename;"
+  UMD_HEADER_ESCAPED=`escape_for_sed_replace "$UMD_HEADER"`
+
+  ES6_FOOTER='export default Box2D;'
+  UMD_FOOTER="if (typeof exports === 'object' && typeof module === 'object')
+      module.exports = Box2D;
+    else if (typeof define === 'function' && define['amd'])
+      define([], function() { return Box2D; });
+    else if (typeof exports === 'object')
+      exports['Box2D'] = Box2D;
+    
+"
+  UMD_FOOTER_ESCAPED=`escape_for_sed_replace "$UMD_FOOTER"`
+
+  sed -e "s/^$ES6_HEADER$/$UMD_HEADER_ESCAPED/" -e "s/^$ES6_FOOTER$/$UMD_FOOTER_ESCAPED/" "$ES_FILE" > "$UMD_FILE"
+  cp "$ES_DIR/$BASENAME.wasm" "$UMD_DIR"
+fi
+>&2 echo -e "${Green}Successfully built $UMD_DIR/$BASENAME.{js,wasm}${NC}\n"