Merge #10534: Clarify prevector::erase and avoid swap-to-clear

e241a63 Clarify prevector::erase and avoid swap-to-clear (Pieter Wuille)

Tree-SHA512: fa7602038feb4417158df13ee7c0351673acf38f8a824e75889710344c46a9b8d5f6059faeb521f73e48b7ad3e1a238a9e433e4b44f7c3b9085ff08ef65271fa
This commit is contained in:
Wladimir J. van der Laan 2017-06-13 18:28:24 +02:00
commit a514ac3dcb
No known key found for this signature in database
GPG key ID: 1E4AED62986CD25D
2 changed files with 9 additions and 2 deletions

View file

@ -387,6 +387,12 @@ public:
} }
iterator erase(iterator first, iterator last) { iterator erase(iterator first, iterator last) {
// Erase is not allowed to the change the object's capacity. That means
// that when starting with an indirectly allocated prevector with
// size and capacity > N, the result may be a still indirectly allocated
// prevector with size <= N and capacity > N. A shrink_to_fit() call is
// necessary to switch to the (more efficient) directly allocated
// representation (with capacity N and size <= N).
iterator p = first; iterator p = first;
char* endp = (char*)&(*end()); char* endp = (char*)&(*end());
if (!std::is_trivially_destructible<T>::value) { if (!std::is_trivially_destructible<T>::value) {

View file

@ -648,8 +648,9 @@ public:
void clear() void clear()
{ {
// The default std::vector::clear() does not release memory. // The default prevector::clear() does not release memory
CScriptBase().swap(*this); CScriptBase::clear();
shrink_to_fit();
} }
}; };