diff options
Diffstat (limited to 'libstdc++-v3/include/ext/rc_string_base.h')
| -rw-r--r-- | libstdc++-v3/include/ext/rc_string_base.h | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/libstdc++-v3/include/ext/rc_string_base.h b/libstdc++-v3/include/ext/rc_string_base.h index c8bb9f3edca..eec6f2dcf0d 100644 --- a/libstdc++-v3/include/ext/rc_string_base.h +++ b/libstdc++-v3/include/ext/rc_string_base.h @@ -175,11 +175,13 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) // with a terminating character and m _CharT elements, it'd // look like this: // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT) + // + sizeof(_Rep) - 1 + // (NB: last two terms for rounding reasons, see _M_create below) // Solving for m: - // m = ((npos - sizeof(_Rep)) / sizeof(_CharT)) - 1 - // In addition, this implementation quarters this amount. - enum { _S_max_size = (((static_cast<size_type>(-1) - sizeof(_Rep)) - / sizeof(_CharT)) - 1) / 4 }; + // m = ((npos - 2 * sizeof(_Rep) + 1) / sizeof(_CharT)) - 1 + // In addition, this implementation halfs this amount. + enum { _S_max_size = (((static_cast<size_type>(-1) - 2 * sizeof(_Rep) + + 1) / sizeof(_CharT)) - 1) / 2 }; // Data Member (private): mutable typename _Util_Base::template _Alloc_hider<_Alloc> _M_dataplus; @@ -386,7 +388,12 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) // meet amortized linear time requirements of the library: see // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html. if (__capacity > __old_capacity && __capacity < 2 * __old_capacity) - __capacity = 2 * __old_capacity; + { + __capacity = 2 * __old_capacity; + // Never allocate a string bigger than _S_max_size. + if (__capacity > size_type(_S_max_size)) + __capacity = size_type(_S_max_size); + } // NB: Need an array of char_type[__capacity], plus a terminating // null char_type() element, plus enough for the _Rep data structure, @@ -401,7 +408,6 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx) { const size_type __extra = __pagesize - __adj_size % __pagesize; __capacity += __extra / sizeof(_CharT); - // Never allocate a string bigger than _S_max_size. if (__capacity > size_type(_S_max_size)) __capacity = size_type(_S_max_size); __size = (__capacity + 1) * sizeof(_CharT) + 2 * sizeof(_Rep) - 1; |