Gentoo's Bugzilla –
Attachment 331758 Details for
Bug 437890app-arch/p7zip-9.13* with sys-devel/gcc-4.7 - ../../Common/../../Common/DynamicBuffer.h:20:5: error: ‘SetCapacity’ was not declared in this scope, and no declarations were found by argument-dependent lookup at the point of instantiation [-fpermissive]