894   } else {
 895     return _space[idx]._addr._base;
 896   }
 897 }
 898 
 899 int FileMapInfo::FileMapHeader::compute_crc() {
 900   char* header = data();
 901   // start computing from the field after _crc
 902   char* buf = (char*)&_crc + sizeof(int);
 903   size_t sz = data_size() - (buf - header);
 904   int crc = ClassLoader::crc32(0, buf, (jint)sz);
 905   return crc;
 906 }
 907 
 908 bool FileMapInfo::FileMapHeader::validate() {
 909   if (VerifySharedSpaces && compute_crc() != _crc) {
 910     fail_continue("Header checksum verification failed.");
 911     return false;
 912   }
 913 
 914   if (Arguments::get_patch_mod_prefix() != NULL) {
 915     FileMapInfo::fail_continue("The shared archive file cannot be used with --patch-module.");
 916     return false;
 917   }
 918 
 919   if (!Arguments::has_jimage()) {
 920     FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
 921     return false;
 922   }
 923 
 924   if (_version != current_version()) {
 925     FileMapInfo::fail_continue("The shared archive file is the wrong version.");
 926     return false;
 927   }
 928   if (_magic != (int)0xf00baba2) {
 929     FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
 930     return false;
 931   }
 932   char header_version[JVM_IDENT_MAX];
 933   get_header_version(header_version);
 934   if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
 935     log_info(class, path)("expected: %s", header_version);
 936     log_info(class, path)("actual:   %s", _jvm_ident);
 937     FileMapInfo::fail_continue("The shared archive file was created by a different"
 938                   " version or build of HotSpot");

 894   } else {
 895     return _space[idx]._addr._base;
 896   }
 897 }
 898 
 899 int FileMapInfo::FileMapHeader::compute_crc() {
 900   char* header = data();
 901   // start computing from the field after _crc
 902   char* buf = (char*)&_crc + sizeof(int);
 903   size_t sz = data_size() - (buf - header);
 904   int crc = ClassLoader::crc32(0, buf, (jint)sz);
 905   return crc;
 906 }
 907 
 908 bool FileMapInfo::FileMapHeader::validate() {
 909   if (VerifySharedSpaces && compute_crc() != _crc) {
 910     fail_continue("Header checksum verification failed.");
 911     return false;
 912   }
 913 





 914   if (!Arguments::has_jimage()) {
 915     FileMapInfo::fail_continue("The shared archive file cannot be used with an exploded module build.");
 916     return false;
 917   }
 918 
 919   if (_version != current_version()) {
 920     FileMapInfo::fail_continue("The shared archive file is the wrong version.");
 921     return false;
 922   }
 923   if (_magic != (int)0xf00baba2) {
 924     FileMapInfo::fail_continue("The shared archive file has a bad magic number.");
 925     return false;
 926   }
 927   char header_version[JVM_IDENT_MAX];
 928   get_header_version(header_version);
 929   if (strncmp(_jvm_ident, header_version, JVM_IDENT_MAX-1) != 0) {
 930     log_info(class, path)("expected: %s", header_version);
 931     log_info(class, path)("actual:   %s", _jvm_ident);
 932     FileMapInfo::fail_continue("The shared archive file was created by a different"
 933                   " version or build of HotSpot");