-------- testcase.cpp --------
template < typename >
struct A {
struct S;
A < S > ht;
};
struct B : A < B > {};
------------------------------
without -ftemplate-depth, it instantiates templates up do default depth, giving
760KiB of diagnostics for this simple testcase (for 4.5.0)
this is output with -ftemplate-depth-5:
$ g++ testcase.cpp -ftemplate-depth-5
testcase.cpp:4: error: template instantiation depth exceeds maximum of 5 (use
-ftemplate-depth-NN to increase the maximum) instantiating 'struct
A<A<A<A<A<A<B>::S>::S>::S>::S>::S>'
testcase.cpp:4: instantiated from 'A<A<A<A<A<B>::S>::S>::S>::S>'
testcase.cpp:4: instantiated from 'A<A<A<A<B>::S>::S>::S>'
testcase.cpp:4: instantiated from 'A<A<A<B>::S>::S>'
testcase.cpp:4: instantiated from 'A<A<B>::S>'
testcase.cpp:4: instantiated from 'A<B>'
testcase.cpp:7: instantiated from here
testcase.cpp:4: error: 'A< <template-parameter-1-1> >::ht' has incomplete type
testcase.cpp:2: error: declaration of 'struct
A<A<A<A<A<A<B>::S>::S>::S>::S>::S>'
------------------------------
all tested gcc versions behave the same - 2.95, 3.2.3, 3.3.6, 3.4.6, 4.0.4,
4.1.2, 4.2.4, 4.3.4, 4.4.3, 4.5.0 (with the exception that 2.95 bails out at
the end, and 3.2.3 and 2.95 need quite long time for even template depth 20)
--
Summary: too long diagnostics in some cases of recursive template
instantiation
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: zsojka at seznam dot cz
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43113
