Bug 3766 – pure, nothrow functions should be subtypes of regular functions

void nothrowStuff() nothrow {} void pureStuff() pure {} void stuff() {} auto funcPtr = (0 == 0) ? &stuff : &nothrowStuff; auto funcPtr2 = (0 == 0) ? &stuff : &pureStuff; test.d(5): Error: incompatible types for ((& stuff) ? (& nothrowStuff)): 'void function()' and 'void function() nothrow' test.d(6): Error: incompatible types for ((& stuff) ? (& pureStuff)): 'void function()' and 'void function() pure' void function() pure and void function() nothrow should be considered subtypes of void function(). A void function() pure or a void function() nothrow simply provides an extra guarantee not present for void function() and thus can be substituted in any context for a void function().

Has been resolved at some point in the last 10 years (!) https://run.dlang.io/is/bZRTNN