Put all prebuild scripts in external files.

build/v8.xcodeproj/project.pbxproj

 // !$*UTF8*$!
 {
         archiveVersion = 1;
         classes = {
         };
         objectVersion = 45;
         objects = {
 
 /* Begin PBXAggregateTarget section */
                 7BF891930E73098D000BAF8A /* All */ = {
@@ skipping 703 matching lines @@
                         path = generated;
                         sourceTree = CONFIGURATION_TEMP_DIR;
                 };
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
                 8970F2EF0E719FB2006AE7B5 /* v8 */ = {
                         isa = PBXNativeTarget;
                         buildConfigurationList = 8970F2F70E719FC1006AE7B5 /* Build configuration list for PBXNativeTarget "v8" */;
                         buildPhases = (
-                                89EA6FB50E71AA1F00F59E1B /* ShellScript */,
+                                89EA6FB50E71AA1F00F59E1B /* Pre-Build */,
                                 8970F2ED0E719FB2006AE7B5 /* Sources */,
                                 8970F2EE0E719FB2006AE7B5 /* Frameworks */,
                         );
                         buildRules = (
                         );
                         dependencies = (
                         );
                         name = v8;
                         productName = v8;
                         productReference = 8970F2F00E719FB2006AE7B5 /* libv8.a */;
@@ skipping 48 matching lines @@
                         targets = (
                                 7BF891930E73098D000BAF8A /* All */,
                                 897FF1BE0E719CB600D62E90 /* jscre */,
                                 8970F2EF0E719FB2006AE7B5 /* v8 */,
                                 897F76790E71B4CC007ACF34 /* v8_shell */,
                         );
                 };
 /* End PBXProject section */
 
 /* Begin PBXShellScriptBuildPhase section */
-                89EA6FB50E71AA1F00F59E1B /* ShellScript */ = {
+                89EA6FB50E71AA1F00F59E1B /* Pre-Build */ = {
                         isa = PBXShellScriptBuildPhase;
                         buildActionMask = 2147483647;
                         files = (
                         );
                         inputPaths = (
                         );
+                        name = "Pre-Build";
                         outputPaths = (
                         );
                         runOnlyForDeploymentPostprocessing = 0;
                         shellPath = /bin/sh;
-                        shellScript = "set -ex\nJS_FILES=\"runtime.js\"\\\n\" v8natives.js\"\\\n\" array.js\"\\\n\" string.js\"\\\n\" uri.js\"\\\n\" math.js\"\\\n\" messages.js\"\\\n\" apinatives.js\"\\\n\" debug-delay.js\"\\\n\" mirror-delay.js\"\\\n\" date-delay.js\"\\\n\" regexp-delay.js\"\\\n\" macros.py\"\n\nV8ROOT=\"${SRCROOT}/../v8\"\n\nSRC_DIR=\"${V8ROOT}/src\"\n\nNATIVE_JS_FILES=\"\"\n\nfor i in ${JS_FILES} ; do\n  NATIVE_JS_FILES+=\"${SRC_DIR}/${i} \"\ndone\n\nV8_GENERATED_SOURCES_DIR=\"${CONFIGURATION_TEMP_DIR}/generated\"\nmkdir -p \"${V8_GENERATED_SOURCES_DIR}\"\n\nLIBRARIES_CC=\"${V8_GENERATED_SOURCES_DIR}/libraries.cc\"\nLIBRARIES_EMPTY_CC=\"${V8_GENERATED_SOURCES_DIR}/libraries-empty.cc\"\n\npython \"${V8ROOT}/tools/js2c.py\" \\\n  \"${LIBRARIES_CC}.new\" \\\n  \"${LIBRARIES_EMPTY_CC}.new\" \\\n  ${NATIVE_JS_FILES}\n\n# Only use the new files if they're different from the existing files (if any),\n# preserving the existing files' timestamps when there are no changes.  This\n# minimizes unnecessary build activity for a no-change build.\n\nif ! diff -q \"${LIBRARIES_CC}.new\" \"${LIBRARIES_CC}\" >& /dev/null ; then\n  mv \"${LIBRARIES_CC}.new\" \"${LIBRARIES_CC}\"\nelse\n  rm \"${LIBRARIES_CC}.new\"\nfi\n\nif ! diff -q \"${LIBRARIES_EMPTY_CC}.new\" \"${LIBRARIES_EMPTY_CC}\" >& /dev/null ; then\n  mv \"${LIBRARIES_EMPTY_CC}.new\" \"${LIBRARIES_EMPTY_CC}\"\nelse\n  rm \"${LIBRARIES_EMPTY_CC}.new\"\nfi\n";
+                        shellScript = "set -ex\nexec \"${PROJECT_FILE_PATH}/${PRODUCT_NAME}_prebuild.sh\" \"${@}\"\n";
+                        showEnvVarsInLog = 0;
                 };
 /* End PBXShellScriptBuildPhase section */
 
 /* Begin PBXSourcesBuildPhase section */
                 8970F2ED0E719FB2006AE7B5 /* Sources */ = {
                         isa = PBXSourcesBuildPhase;
                         buildActionMask = 2147483647;
                         files = (
                                 89A88DEC0E71A5FF0043BA31 /* accessors.cc in Sources */,
                                 89A88DED0E71A6000043BA31 /* allocation.cc in Sources */,
@@ skipping 263 matching lines @@
                                 897FF1C10E719CB600D62E90 /* Debug */,
                                 897FF1C20E719CB600D62E90 /* Release */,
                         );
                         defaultConfigurationIsVisible = 0;
                         defaultConfigurationName = Release;
                 };
 /* End XCConfigurationList section */
         };
         rootObject = 8915B8680E719336009C4E19 /* Project object */;
 }