Fix KiCad WASM build and runtime errors

Build improvements:
- Change -O0 to -O1 to fix "local count too large" asyncify error
- Add wasm-emscripten-finalize to host (Docker OOMs on large WASM)
- Use -gseparate-dwarf for smaller main binary with debug info
- Build native protoc for code generation
- Add more functions to asyncify removelist

Runtime fixes:
- Add inject-dyncall-shims.sh to fix "dynCall_* is not defined" in Emscripten 4.x
- Update wxwidgets with browserInfo.name fix

New stubs and bindings:
- Add Embind bindings for JavaScript interop
- Add stubs for scripting, API plugin, PCB frame, navlib

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/build-wxuniversal-wasm.sh

@@ -83,7 +83,7 @@ PCRE2_INCLUDE="$BUILD_DIR/3rdparty/pcre/src"
 
 # Configure debug/release flags based on DEBUG_BUILD environment variable
 if [ "${DEBUG_BUILD:-1}" = "1" ]; then
-    WX_DEBUG_FLAGS="-g -O0"
+    WX_DEBUG_FLAGS="-g -O1"
     WX_CONFIGURE_DEBUG="--enable-debug"
     echo "Building wxWidgets in DEBUG mode"
 else

scripts/common/apply-asyncify.sh

@@ -39,6 +39,13 @@ ASYNCIFY_REMOVE=$(cat << 'REMOVELIST'
 COLOR_SETTINGS::COLOR_SETTINGS(wxString const&, bool)
 BuildBitmapInfo(std::__2::unordered_map<BITMAPS, std::__2::vector<BITMAP_INFO, std::__2::allocator<BITMAP_INFO>>, std::__2::hash<BITMAPS>, std::__2::equal_to<BITMAPS>, std::__2::allocator<std::__2::pair<BITMAPS const, std::__2::vector<BITMAP_INFO, std::__2::allocator<BITMAP_INFO>>>>>&)
 match
+DIALOG_PAD_PROPERTIES_BASE::DIALOG_PAD_PROPERTIES_BASE(wxWindow*, int, wxString const&, wxPoint const&, wxSize const&, long)
+buildKicadAboutBanner(EDA_BASE_FRAME*, ABOUT_APP_INFO&)
+IGESToBRep_CurveAndSurface::TransferGeometry(opencascade::handle<IGESData_IGESEntity> const&, Message_ProgressRange const&)
+StepAP214_Protocol::StepAP214_Protocol()
+BRepCheck_ParallelAnalyzer::operator()(int) const
+ShapeFix_Wire::FixGap3d(int, bool)
+ShapeFix_Wire::FixGap2d(int, bool)
 REMOVELIST
 )
 

scripts/common/apply-finalize.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+# Apply wasm-emscripten-finalize transformation on host
+# Uses the same Binaryen v121 as wasm-opt to ensure version consistency
+#
+# Usage: ./scripts/common/apply-finalize.sh <input.wasm> <output.wasm>
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
+
+# Get wasm-emscripten-finalize from same Binaryen install as wasm-opt
+BINARYEN_DIR="${PROJECT_ROOT}/tools/binaryen-121"
+FINALIZE="${BINARYEN_DIR}/bin/wasm-emscripten-finalize"
+
+# Ensure Binaryen is downloaded
+if [ ! -x "${FINALIZE}" ]; then
+    echo "Downloading Binaryen v121..."
+    "${SCRIPT_DIR}/get-wasm-opt.sh" > /dev/null
+fi
+
+INPUT_WASM="${1:-output/pcbnew.wasm}"
+OUTPUT_WASM="${2:-${INPUT_WASM}}"
+
+if [ ! -f "${INPUT_WASM}" ]; then
+    echo "ERROR: Input file not found: ${INPUT_WASM}"
+    exit 1
+fi
+
+echo "Applying wasm-emscripten-finalize..."
+echo "  Input:  ${INPUT_WASM}"
+echo "  Output: ${OUTPUT_WASM}"
+echo "  Tool:   ${FINALIZE}"
+
+# Run finalize with the same flags Emscripten would use
+# NOTE: --dwarf removed because debug info is in separate .debug.wasm file
+"${FINALIZE}" \
+    -g \
+    --bigint \
+    --no-legalize-javascript-ffi \
+    --detect-features \
+    "${INPUT_WASM}" \
+    -o "${OUTPUT_WASM}"
+
+echo "Finalize complete: ${OUTPUT_WASM}"
+ls -lh "${OUTPUT_WASM}"

scripts/common/env.sh

@@ -40,7 +40,7 @@ DEBUG_BUILD="${DEBUG_BUILD:-1}"
 
 if [ "$DEBUG_BUILD" = "1" ]; then
     export BUILD_TYPE="Debug"
-    export DEBUG_CFLAGS="-g -O0"
+    export DEBUG_CFLAGS="-g -O1"
     export DEBUG_LDFLAGS="-g -gsource-map"
 else
     export BUILD_TYPE="Release"

scripts/common/inject-dyncall-shims.sh

@@ -0,0 +1,114 @@
+#!/bin/bash
+# Inject dynCall_* shims into Emscripten-generated JS
+#
+# Emscripten 4.x no longer generates signature-specific dynCall_* functions,
+# but the invoke_* wrappers (for C++ exception handling) still call them.
+# This script auto-generates shims using getWasmTableEntry() which IS defined.
+#
+# Usage: inject-dyncall-shims.sh <pcbnew.js>
+
+set -e
+
+JS_FILE="$1"
+
+if [ -z "$JS_FILE" ] || [ ! -f "$JS_FILE" ]; then
+    echo "Error: JS file not found: $JS_FILE"
+    echo "Usage: $0 <path/to/pcbnew.js>"
+    exit 1
+fi
+
+echo "Extracting dynCall signatures from $JS_FILE..."
+
+# Extract all unique dynCall_* signatures from the file
+# Matches patterns like: dynCall_i, dynCall_ii, dynCall_viijj, etc.
+SIGNATURES=$(grep -oE 'dynCall_[a-zA-Z0-9]+' "$JS_FILE" | sort -u | sed 's/dynCall_//')
+
+if [ -z "$SIGNATURES" ]; then
+    echo "No dynCall signatures found - nothing to inject"
+    exit 0
+fi
+
+SIG_COUNT=$(echo "$SIGNATURES" | wc -l | tr -d ' ')
+echo "Found $SIG_COUNT unique signatures"
+
+# Generate shim code
+SHIM_FILE=$(mktemp)
+cat > "$SHIM_FILE" << 'HEADER'
+
+// === dynCall shims for Emscripten exception handling ===
+// Auto-generated: maps dynCall_SIG() calls to getWasmTableEntry()
+// This fixes "dynCall_* is not defined" errors in Emscripten 4.x
+HEADER
+
+for sig in $SIGNATURES; do
+    # Count args: signature length - 1 (first char is return type)
+    argcount=$((${#sig} - 1))
+
+    # Generate argument list: index, a0, a1, a2, ...
+    args="index"
+    call_args=""
+    for ((i=0; i<argcount; i++)); do
+        args="$args, a$i"
+        if [ $i -gt 0 ]; then
+            call_args="$call_args, "
+        fi
+        call_args="${call_args}a$i"
+    done
+
+    echo "var dynCall_$sig = ($args) => getWasmTableEntry(index)($call_args);" >> "$SHIM_FILE"
+done
+
+echo "" >> "$SHIM_FILE"
+echo "// === End dynCall shims ===" >> "$SHIM_FILE"
+
+# Find the insertion point: after getWasmTableEntry definition
+# The pattern is:
+#   var getWasmTableEntry = funcPtr => {
+#     ...
+#   };
+# We insert after the closing `};`
+
+# Find line number of getWasmTableEntry definition
+GWTL_LINE=$(grep -n '^var getWasmTableEntry = funcPtr => {' "$JS_FILE" | head -1 | cut -d: -f1)
+
+if [ -z "$GWTL_LINE" ]; then
+    echo "Warning: Could not find getWasmTableEntry definition"
+    echo "Trying alternate pattern..."
+    GWTL_LINE=$(grep -n 'var getWasmTableEntry' "$JS_FILE" | head -1 | cut -d: -f1)
+fi
+
+if [ -z "$GWTL_LINE" ]; then
+    echo "Error: Could not find getWasmTableEntry in $JS_FILE"
+    echo "The shims need to be inserted after getWasmTableEntry is defined"
+    rm "$SHIM_FILE"
+    exit 1
+fi
+
+# Find the closing `};` after getWasmTableEntry (within next 10 lines)
+INSERT_LINE=""
+for ((i=GWTL_LINE; i<=GWTL_LINE+10; i++)); do
+    LINE_CONTENT=$(sed -n "${i}p" "$JS_FILE")
+    if [[ "$LINE_CONTENT" == "};" ]]; then
+        INSERT_LINE=$i
+        break
+    fi
+done
+
+if [ -z "$INSERT_LINE" ]; then
+    echo "Warning: Could not find closing }; for getWasmTableEntry"
+    echo "Inserting after line $GWTL_LINE"
+    INSERT_LINE=$GWTL_LINE
+fi
+
+echo "Injecting shims after line $INSERT_LINE..."
+
+# Create output file with shims inserted
+head -n "$INSERT_LINE" "$JS_FILE" > "${JS_FILE}.tmp"
+cat "$SHIM_FILE" >> "${JS_FILE}.tmp"
+tail -n +$((INSERT_LINE + 1)) "$JS_FILE" >> "${JS_FILE}.tmp"
+
+# Replace original file
+mv "${JS_FILE}.tmp" "$JS_FILE"
+rm "$SHIM_FILE"
+
+echo "Successfully injected $SIG_COUNT dynCall shims into $JS_FILE"

scripts/deps/build-protobuf.sh

@@ -49,8 +49,37 @@ if [ ! -d "${PROTOBUF_DIR}" ]; then
     rm "protobuf-${PROTOBUF_VERSION}.tar.gz"
 fi
 
-log_info "Building Protobuf ${PROTOBUF_VERSION} for WASM..."
+log_info "Building Protobuf ${PROTOBUF_VERSION}..."
 
+# Step 1: Build native protoc for the host (needed for code generation)
+# This is required because the system protoc may be a different version
+PROTOBUF_HOST_BUILD="${BUILD_ROOT}/deps/protobuf-host"
+PROTOC_NATIVE="${PROTOBUF_HOST_BUILD}/protoc"
+
+if [ ! -f "${PROTOC_NATIVE}" ]; then
+    log_info "Building native protoc for host..."
+    mkdir -p "${PROTOBUF_HOST_BUILD}"
+    cd "${PROTOBUF_HOST_BUILD}"
+
+    # Build native (not cross-compiled) protoc
+    cmake "${PROTOBUF_DIR}" \
+        -DCMAKE_BUILD_TYPE=Release \
+        -Dprotobuf_BUILD_TESTS=OFF \
+        -Dprotobuf_BUILD_EXAMPLES=OFF \
+        -Dprotobuf_BUILD_SHARED_LIBS=OFF \
+        -Dprotobuf_WITH_ZLIB=OFF
+
+    make -j${JOBS} protoc
+    log_info "Native protoc built: ${PROTOC_NATIVE}"
+fi
+
+# Install native protoc to sysroot/bin for CMake to find
+mkdir -p "${SYSROOT}/bin"
+cp "${PROTOC_NATIVE}" "${SYSROOT}/bin/protoc"
+log_info "Native protoc installed to ${SYSROOT}/bin/protoc"
+
+# Step 2: Build WASM library
+log_info "Building Protobuf library for WASM..."
 mkdir -p "${PROTOBUF_BUILD}"
 cd "${PROTOBUF_BUILD}"
 

scripts/kicad/build-pcbnew.sh

@@ -127,11 +127,11 @@ log_info "Building KiCad PCBnew ${KICAD_VERSION} for WASM..."
 if [ "${DEBUG_BUILD:-0}" = "1" ] || [ $DEBUG -eq 1 ]; then
     BUILD_TYPE="Debug"
     EXTRA_FLAGS="-g -O1 -fexceptions -matomics -mbulk-memory"
-    # -O0 at link time skips wasm-opt (which can OOM on large WASM with debug symbols)
-    # NOTE: -gsource-map removed because wasm-emscripten-finalize OOMs on large WASM
-    # with source maps enabled. Keep -g for debug symbols in the WASM.
-    LINKER_DEBUG_FLAGS="-O0 -g -fexceptions"
-    log_info "Building KiCad in DEBUG mode (debug symbols, no source maps due to memory)"
+    # -gseparate-dwarf puts debug info in a separate .debug.wasm file
+    # This keeps the main WASM small (~200MB) while preserving full debug info
+    # DevTools loads the debug file on-demand when debugging
+    LINKER_DEBUG_FLAGS="-O1 -g -gseparate-dwarf -fexceptions"
+    log_info "Building KiCad in DEBUG mode (separate DWARF for smaller main binary)"
 else
     BUILD_TYPE="Release"
     EXTRA_FLAGS="-O2 -fexceptions -matomics -mbulk-memory"
@@ -187,6 +187,18 @@ cp "${STUBS_DIR}/wasm-opt-stub.sh" "${EMSDK_WASM_OPT}"
 chmod +x "${EMSDK_WASM_OPT}"
 log_info "wasm-opt stub installed (asyncify will run on host)"
 
+# Step 6.3: Replace wasm-emscripten-finalize with stub (same pattern as wasm-opt)
+# This tool also OOMs on large WASM with debug symbols, so we run it on the host
+EMSDK_FINALIZE="/emsdk/upstream/bin/wasm-emscripten-finalize"
+if [ -f "${EMSDK_FINALIZE}" ] && [ ! -f "${EMSDK_FINALIZE}.real" ]; then
+    log_info "Backing up real wasm-emscripten-finalize..."
+    mv "${EMSDK_FINALIZE}" "${EMSDK_FINALIZE}.real"
+fi
+# Always copy the latest stub (in case it was updated)
+cp "${STUBS_DIR}/wasm-emscripten-finalize-stub.sh" "${EMSDK_FINALIZE}"
+chmod +x "${EMSDK_FINALIZE}"
+log_info "wasm-emscripten-finalize stub installed (finalize will run on host)"
+
 # Step 6.5: Verify WASM support is in KiCad fork
 # The kicad submodule should already have WASM port detection and kiplatform support
 KICAD_CMAKE="${KICAD_DIR}/CMakeLists.txt"
@@ -214,7 +226,7 @@ emcmake cmake "${KICAD_DIR}" \
     -DCMAKE_POLICY_VERSION_MINIMUM=3.5 \
     -DCMAKE_CXX_FLAGS="${EXTRA_FLAGS} -pthread -sUSE_ZLIB=1 -DKICAD_USE_PLATFORM_WASM=1 -I${SYSROOT}/include -I${STUBS_DIR}" \
     -DCMAKE_C_FLAGS="${EXTRA_FLAGS} -pthread -sUSE_ZLIB=1 -I${SYSROOT}/include -I${STUBS_DIR}" \
-    -DCMAKE_EXE_LINKER_FLAGS="${LINKER_DEBUG_FLAGS} -pthread -sUSE_ZLIB=1 -sASYNCIFY=1 -sASYNCIFY_STACK_SIZE=65536 -sUSE_PTHREADS=1 -sPTHREAD_POOL_SIZE='navigator.hardwareConcurrency' -sPTHREAD_POOL_SIZE_STRICT=0 -sALLOW_MEMORY_GROWTH=1 -sINITIAL_MEMORY=256MB -sMAXIMUM_MEMORY=4GB -sEXPORTED_RUNTIME_METHODS=['ccall','cwrap','UTF8ToString','stringToUTF8','lengthBytesUTF8'] -L${SYSROOT}/lib ${STUBS_BUILD}/libgit2_stub.a ${STUBS_BUILD}/libcurl_stub.a ${STUBS_BUILD}/libglu_stub.a ${STUBS_BUILD}/libpcbnew_scripting_stub.a ${STUBS_BUILD}/libnng_stub.a" \
+    -DCMAKE_EXE_LINKER_FLAGS="${LINKER_DEBUG_FLAGS} -pthread -sUSE_ZLIB=1 -sASYNCIFY=1 -sDYNCALLS=1 -sASYNCIFY_STACK_SIZE=65536 -sUSE_PTHREADS=1 -sPTHREAD_POOL_SIZE='navigator.hardwareConcurrency' -sPTHREAD_POOL_SIZE_STRICT=0 -sALLOW_MEMORY_GROWTH=1 -sINITIAL_MEMORY=256MB -sMAXIMUM_MEMORY=4GB -sEXPORTED_RUNTIME_METHODS=['ccall','cwrap','UTF8ToString','stringToUTF8','lengthBytesUTF8','dynCall'] -sDEFAULT_LIBRARY_FUNCS_TO_INCLUDE=['\$dynCall'] --bind -L${SYSROOT}/lib ${STUBS_BUILD}/libgit2_stub.a ${STUBS_BUILD}/libcurl_stub.a ${STUBS_BUILD}/libglu_stub.a ${STUBS_BUILD}/libpcbnew_scripting_stub.a ${STUBS_BUILD}/libnng_stub.a ${STUBS_BUILD}/pcbnew_embind.o" \
     -DCMAKE_PREFIX_PATH="${SYSROOT};${WX_BUILD}" \
     -DwxWidgets_CONFIG_EXECUTABLE="${WX_BUILD}/wx-config" \
     \
@@ -252,7 +264,29 @@ emcmake cmake "${KICAD_DIR}" \
     -DODBC_LIBRARIES:STRING="" \
     \
     -DBUILD_GITHUB_PLUGIN=OFF \
-    -DKICAD_PCM=OFF
+    -DKICAD_PCM=OFF \
+    \
+    -DHAVE_STRCASECMP=1 \
+    -DHAVE_STRNCASECMP=1
+
+# Step 7.1: Compile Embind bindings (after CMake so config.h exists)
+# Exposes KiCad objects to JavaScript for future Pyodide integration
+EMBIND_SRC="${PROJECT_ROOT}/wasm/bindings/pcbnew_embind.cpp"
+if [ -f "$EMBIND_SRC" ]; then
+    log_info "Compiling Embind bindings..."
+    # Use the same includes and flags that KiCad uses
+    KICAD_INCLUDES="-I${KICAD_BUILD} -I${KICAD_DIR}/include -I${KICAD_DIR}/pcbnew -I${KICAD_DIR}/common"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/libs/core/include -I${KICAD_DIR}/libs/kimath/include -I${KICAD_DIR}/libs/kiplatform/include"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty/clipper2/Clipper2Lib/include"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty/nlohmann_json"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty/dynamic_bitset"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty/nanodbc"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty/picosha2"
+    KICAD_INCLUDES+=" -I${KICAD_DIR}/thirdparty"
+    KICAD_INCLUDES+=" -I${SYSROOT}/include"
+    # KiCad requires C++20 for concepts
+    em++ -std=c++20 -c ${EXTRA_FLAGS} ${WX_CXXFLAGS} ${KICAD_INCLUDES} "$EMBIND_SRC" -o "${STUBS_BUILD}/pcbnew_embind.o"
+fi
 
 # Step 8: Build pcbnew target
 log_info "Building pcbnew..."