[Bug c++/126811] [14/15/16/17 Regression] c++: ICE in tsubst when a constexpr init contains an NSDMI

[iains at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126811

--- Comment #3 from Iain Sandoe <iains at gcc dot gnu.org> ---
the case for FIX_TRUNC_EXPR says :

/* convert_like should have created an IMPLICIT_CONV_EXPR.  */
 gcc_unreachable ();

So maybe the issue is caller-side...  (there is no handling for FLOAT_EXPR at
all and it hits an unreachable independently).