http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16564
--- Comment #19 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Volker Reichelt from comment #18)
> The first error message about exceeding the maximum template instantiation
> depth appears rather quickly. So maybe we could make the first error message
> a fatal one to avoid further processing of potentially bogus nested classes.
It seems to me GCC is doing something strange. See comment #14. But what you
suggest seems to be what Clang++ is doing:
$ /usr/bin/time clang++ test.cc
test.cc:3:8: fatal error: recursive template instantiation exceeded maximum
depth of 256
A<A> a;
^
test.cc:3:8: note: in instantiation of template class
'...' requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class
'...' requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class
'...' requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class
'...' requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class
'...' requested here
A<A> a;
^
test.cc:3:8: note: (skipping 247 contexts in backtrace; use
-ftemplate-backtrace-limit=0 to see all)
test.cc:3:8: note: in instantiation of template class 'A<A<A<A<A<int> > > > >'
requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class 'A<A<A<A<int> > > >'
requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class 'A<A<A<int> > >'
requested here
A<A> a;
^
test.cc:3:8: note: in instantiation of template class 'A<A<int> >' requested
here
A<A> a;
^
test.cc:7:8: note: in instantiation of template class 'A<int>' requested here
A<int> a;
^
test.cc:3:8: note: use -ftemplate-depth=N to increase recursive template
instantiation depth
A<A> a;
^
1 error generated.
Command exited with non-zero status 1
0.11user 0.02system 0:00.14elapsed 96%CPU (0avgtext+0avgdata 67904maxresident)k
0inputs+0outputs (0major+6524minor)pagefaults 0swaps
And GCC's output in recent versions would look better than this because it has
automatic recursion detection:
test.cc:3:8: error: template instantiation depth exceeds maximum of 900 (use
-ftemplate-depth= to increase the maximum) instantiating ‘struct ...’
A<A> a;
^
test.cc:3:8: recursively required from ‘struct A<A<int> >’
test.cc:3:8: required from ‘struct A<int>’
test.cc:7:8: required from here
