http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55914
Bug #: 55914
Summary: [C++11] Pack expansion for class member expression
fails in lambda expressions
Classification: Unclassified
Product: gcc
Version: 4.7.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: [email protected]
ReportedBy: [email protected]
The following code, compiled with
-Wall -std=c++11 -pedantic
is rejected by gcc 4.7.2 and gcc 4.8.0 20130106 (experimental):
//---------------------
struct S {
int foo(){ return 0; }
};
template<class... Args>
void evaluate(Args...){}
template <class... Args>
void bar(Args... args) {
evaluate(args.foo()...); // OK
auto lmb = [=](){ evaluate(args.foo()...); }; // Error
lmb();
}
int main() {
S s{};
bar(s);
}
//---------------------
"11|error: parameter packs not expanded with '...':|
11|note: 'args'|
In instantiation of 'void bar(Args ...) [with Args = {S}]':|
17|required from here|
11|error: using invalid field 'bar(Args ...)::__lambda0::__args'|
"
The problem also occurs for class member expressions of the form E1->E2 instead
of E1.E2.
