Which-function no longer works when imenu-sort-function not nil

[Richard . G . Bielawski]

When imenu-sort-function's value is non-nil (for example set to
imenu--sort-by-name) 
which-function displays the function whose name is alphabetically highest
prior to point.
For example:
-------------------buffer start
/* int x(); */
int firstFcn();

int secondFcn();

main();

-----------------buffer end
When point enters 'main' which-function continues to display 'secondFcn'
because m is alphabetically prior to s.
If I uncomment int x(); which-function would display 'x' until the end of
the buffer.

Richard Bielawski
612-667-5039

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