http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56437
Bug #: 56437
Summary: basic_string assumes that allocators are
default-constructible
Classification: Unclassified
Product: gcc
Version: 4.8.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: tneum...@pi3.informatik.uni-mannheim.de
Created attachment 29531
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29531
example
The empty-string optimization of basic_string assumes that allocators are
default constructible. While this used to be the case in C++98, it is no longer
true in C++11, as now allocators are allowed to have state.
Consider the attached example program. Compiling with
g++ -std=c++11 -c t.cpp
produces an error message, even though it should compile fine. The problem is
the the "_S_construct" calls "_Alloc()", which does not exist.
Note that the C++11 standard does not require default constructors. (Section
17.6.3.5, Table 28). In particular, the SimpleAllocator example from Section
17.6.3.5 would trigger the same bug, too.
