chore: strip release bb binaries and hide static library symbols

Author: AztecBot

barretenberg/cpp/CMakePresets.json

@@ -42,8 +42,9 @@
       "environment": {
         "CC": "${sourceDir}/scripts/zig-cc.sh",
         "CXX": "${sourceDir}/scripts/zig-c++.sh",
-        "CFLAGS": "-g0",
-        "CXXFLAGS": "-g0"
+        "CFLAGS": "-g0 -fvisibility=hidden",
+        "CXXFLAGS": "-g0 -fvisibility=hidden",
+        "LDFLAGS": "-s"
       },
       "cacheVariables": {
         "CMAKE_AR": "${sourceDir}/scripts/zig-ar.sh",
@@ -407,8 +408,7 @@
         "WASI_SDK_PREFIX": "/opt/wasi-sdk",
         "CC": "$env{WASI_SDK_PREFIX}/bin/clang",
         "CXX": "$env{WASI_SDK_PREFIX}/bin/clang++",
-        "CXXFLAGS": "-DBB_VERBOSE",
-        "LDFLAGS": "--no-wasm-opt",
+        "CXXFLAGS": "-DBB_VERBOSE -fvisibility=hidden",
         "AR": "$env{WASI_SDK_PREFIX}/bin/llvm-ar",
         "RANLIB": "$env{WASI_SDK_PREFIX}/bin/llvm-ranlib"
       },
@@ -468,8 +468,8 @@
       "environment": {
         "CC": "zig cc",
         "CXX": "zig c++",
-        "CFLAGS": "-g0",
-        "CXXFLAGS": "-g0"
+        "CFLAGS": "-g0 -fvisibility=hidden",
+        "CXXFLAGS": "-g0 -fvisibility=hidden"
       },
       "cacheVariables": {
         "ENABLE_PIC": "ON",
@@ -514,7 +514,8 @@
       "inherits": "cross-base",
       "environment": {
         "CC": "zig cc -target x86_64-macos -mcpu=baseline",
-        "CXX": "zig c++ -target x86_64-macos -mcpu=baseline"
+        "CXX": "zig c++ -target x86_64-macos -mcpu=baseline",
+        "LDFLAGS": "-s"
       },
       "cacheVariables": {
         "CMAKE_SYSTEM_NAME": "Darwin",
@@ -530,7 +531,8 @@
       "inherits": "cross-base",
       "environment": {
         "CC": "zig cc -target aarch64-macos -mcpu=apple_a14",
-        "CXX": "zig c++ -target aarch64-macos -mcpu=apple_a14"
+        "CXX": "zig c++ -target aarch64-macos -mcpu=apple_a14",
+        "LDFLAGS": "-s"
       },
       "cacheVariables": {
         "CMAKE_SYSTEM_NAME": "Darwin",

barretenberg/cpp/bootstrap.sh

@@ -198,17 +198,15 @@ function build_release_dir {
 
   # Wasm.
   tar -czf build-release/barretenberg-wasm.tar.gz -C build-wasm/bin barretenberg.wasm
-  tar -czf build-release/barretenberg-debug-wasm.tar.gz -C build-wasm/bin barretenberg-debug.wasm
   tar -czf build-release/barretenberg-threads-wasm.tar.gz -C build-wasm-threads/bin barretenberg.wasm
-  tar -czf build-release/barretenberg-threads-debug-wasm.tar.gz -C build-wasm-threads/bin barretenberg-debug.wasm
 
   # bb cross-compiles.
   tar -czf build-release/barretenberg-arm64-linux.tar.gz -C build-arm64-linux/bin bb
   tar -czf build-release/barretenberg-arm64-darwin.tar.gz -C build-arm64-macos/bin bb
   tar -czf build-release/barretenberg-amd64-darwin.tar.gz -C build-amd64-macos/bin bb
   tar -czf build-release/barretenberg-amd64-windows.tar.gz -C build-amd64-windows/bin bb.exe
 
-  # Package static libraries for FFI bindings.
+  # Package static libraries for FFI bindings (stripped at build time via CMake POST_BUILD).
   tar -czf build-release/barretenberg-static-amd64-linux.tar.gz -C $native_build_dir/lib libbb-external.a
   tar -czf build-release/barretenberg-static-arm64-linux.tar.gz -C build-arm64-linux/lib libbb-external.a
   tar -czf build-release/barretenberg-static-amd64-darwin.tar.gz -C build-amd64-macos/lib libbb-external.a

barretenberg/cpp/src/CMakeLists.txt

@@ -197,6 +197,9 @@ set(BARRETENBERG_TARGET_OBJECTS
     $<TARGET_OBJECTS:translator_vm_objects>
     $<TARGET_OBJECTS:ultra_honk_objects>)
 
+# Save the core object list before adding lmdb/world_state (not needed by FFI consumers).
+set(BB_EXTERNAL_TARGET_OBJECTS ${BARRETENBERG_TARGET_OBJECTS})
+
 if(NOT WASM AND NOT FUZZING AND NOT BB_LITE)
     # enable merkle trees and lmdb (not for mobile builds)
     list(APPEND BARRETENBERG_TARGET_OBJECTS $<TARGET_OBJECTS:crypto_merkle_tree_objects>)
@@ -211,17 +214,35 @@ add_library(
     ${BARRETENBERG_TARGET_OBJECTS}
 )
 
-# bb-external: A complete static library for external consumers (e.g. barretenberg-rs).
-# Includes everything from libbarretenberg.a plus env and vm2_stub.
-# This provides a single library file that external bindings can link against.
+# bb-external: static library for external consumers (e.g. barretenberg-rs).
+# Uses the core object list without lmdb/world_state — FFI consumers only need bbapi().
+# Built with -fvisibility=hidden; only WASM_EXPORT symbols remain visible.
+# Post-build step merges objects and strips non-exported symbols.
 if(NOT WASM)
     add_library(
         bb-external
         STATIC
-        ${BARRETENBERG_TARGET_OBJECTS}
+        ${BB_EXTERNAL_TARGET_OBJECTS}
         $<TARGET_OBJECTS:env_objects>
         $<TARGET_OBJECTS:vm2_stub>
     )
+
+    # Post-build: merge all objects and strip non-WASM_EXPORT symbols.
+    # Only symbols marked WASM_EXPORT (visibility("default")) survive.
+    find_program(LLD_LINKER NAMES ld.lld-20 ld.lld REQUIRED)
+    find_program(LLVM_OBJCOPY NAMES llvm-objcopy-20 llvm-objcopy REQUIRED)
+    find_program(LLVM_STRIP NAMES llvm-strip-20 llvm-strip REQUIRED)
+    find_program(LLVM_AR_TOOL NAMES llvm-ar-20 llvm-ar REQUIRED)
+    add_custom_command(TARGET bb-external POST_BUILD
+        COMMAND ${LLD_LINKER} -r --whole-archive $<TARGET_FILE:bb-external> $<TARGET_FILE:libdeflate::libdeflate_static> -o $<TARGET_FILE:bb-external>.merged.o
+        COMMAND ${LLVM_OBJCOPY} --localize-hidden $<TARGET_FILE:bb-external>.merged.o
+        COMMAND ${LLVM_STRIP} --strip-unneeded $<TARGET_FILE:bb-external>.merged.o
+        COMMAND ${CMAKE_COMMAND} -E rm -f $<TARGET_FILE:bb-external>
+        COMMAND ${LLVM_AR_TOOL} rcs $<TARGET_FILE:bb-external> $<TARGET_FILE:bb-external>.merged.o
+        COMMAND ${CMAKE_COMMAND} -E rm -f $<TARGET_FILE:bb-external>.merged.o
+        COMMENT "Stripping internal symbols from bb-external static library"
+        VERBATIM
+    )
 endif()
 
 if(WASM)

barretenberg/cpp/src/barretenberg/env/data_store.cpp

@@ -1,5 +1,6 @@
 #include "hardware_concurrency.hpp"
 #include <barretenberg/common/throw_or_abort.hpp>
+#include <barretenberg/common/wasm_export.hpp>
 #include <cstdlib>
 #include <iostream>
 #include <stdexcept>
@@ -9,14 +10,12 @@
 #include <thread>
 #endif
 
-extern "C" {
-
-uint32_t env_hardware_concurrency()
+// WASM_EXPORT ensures this symbol stays visible when compiling with -fvisibility=hidden.
+WASM_EXPORT uint32_t env_hardware_concurrency()
 {
 #ifdef NO_MULTITHREADING
     return 1;
 #else
     return std::thread::hardware_concurrency();
 #endif
 }
-}

barretenberg/cpp/src/barretenberg/env/data_store.hpp

@@ -65,7 +65,9 @@ std::size_t peak_rss_bytes()
 //     interleave if multiple threads call concurrently (as with any
 //     stderr logging).
 //---------------------------------------------------------------------
-extern "C" void logstr(char const* msg)
+// WASM_EXPORT ensures this symbol stays visible when compiling with -fvisibility=hidden.
+#include <barretenberg/common/wasm_export.hpp>
+WASM_EXPORT void logstr(char const* msg)
 {
 #ifndef NO_MULTITHREADING
     static std::mutex log_mutex;

barretenberg/cpp/src/barretenberg/env/hardware_concurrency.cpp

@@ -1,4 +1,5 @@
 #include "barretenberg/common/log.hpp"
+#include "barretenberg/common/wasm_export.hpp"
 #include <stdexcept>
 #ifdef STACKTRACES
 #include <backward.hpp>
@@ -10,8 +11,8 @@ inline void abort_with_message [[noreturn]] (std::string const& err)
     std::abort();
 }
 
-// Native implementation of throw_or_abort
-extern "C" void throw_or_abort_impl [[noreturn]] (const char* err)
+// WASM_EXPORT ensures this symbol stays visible when compiling with -fvisibility=hidden.
+WASM_EXPORT void throw_or_abort_impl [[noreturn]] (const char* err)
 {
 
 #ifdef STACKTRACES

barretenberg/cpp/src/barretenberg/env/logstr.cpp

@@ -5,7 +5,7 @@ import { randomBytes } from '../../random/index.js';
  * Contains code that is common to the "main thread" implementation and the "child thread" implementation.
  */
 export class BarretenbergWasmBase {
-  protected memStore: { [key: string]: Uint8Array } = {};
+
   protected memory!: WebAssembly.Memory;
   protected instance!: WebAssembly.Instance;
   protected logger: (msg: string) => void = () => {};
@@ -55,26 +55,6 @@ export class BarretenbergWasmBase {
           throw new Error(str);
         },
 
-        get_data: (keyAddr: number, outBufAddr: number) => {
-          const key = this.stringFromAddress(keyAddr);
-          outBufAddr = outBufAddr >>> 0;
-          const data = this.memStore[key];
-          if (!data) {
-            this.logger(`get_data miss ${key}`);
-            return;
-          }
-          // this.logger(`get_data hit ${key} size: ${data.length} dest: ${outBufAddr}`);
-          // this.logger(Buffer.from(data.slice(0, 64)).toString('hex'));
-          this.writeMemory(outBufAddr, data);
-        },
-
-        set_data: (keyAddr: number, dataAddr: number, dataLength: number) => {
-          const key = this.stringFromAddress(keyAddr);
-          dataAddr = dataAddr >>> 0;
-          this.memStore[key] = this.getMemorySlice(dataAddr, dataAddr + dataLength);
-          // this.logger(`set_data: ${key} length: ${dataLength}`);
-        },
-
         memory,
       },
     };