[Bug c++/88419] [7/8/9 Regression] [ICE] "Same canonical type node for different types" for CTAD in noexcept

[Casey at Carter dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88419

Casey Carter <Casey at Carter dot net> changed:

           What    |Removed                     |Added
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           Keywords|accepts-invalid             |

--- Comment #6 from Casey Carter <Casey at Carter dot net> ---
Clarifying: 

The sample TU is valid; It's rejected by GCC 6 because that version does not
support C++17 class template argument deduction. 

I claim that the bug is a regression because 7/8 compile it correctly in
default mode, and 9 does not. Yes, it's incorrectly rejected by 7 and 8 as well
when compiling with -fchecking=1, so it's *not* a regression that 9 rejects the
code with -fchecking=1.