• Simon Peyton Jones's avatar
    Report a Wanted error even if there are Given ones · a49f95c2
    Simon Peyton Jones authored
    We suppress some Given errors; see Note [Given errors]
    in TcErrors.  But we must be careful not to suppress
    Wanted errors because of the presence of these Given
    errors -- else we might allow compilation to bogusly
    proceed
    
    The rubber hits the road in TcRnTypes.insolubleCt,
    where we don't want to treat Givens as insoluble,
    nor (and this is the new bit) Deriveds that arise
    from Givens.  See Note [Given insolubles] in TcRnTypes.
    
    This fixes #15767.
    
    (cherry picked from commit 6b1102e2)
    
    Ben notes:
    
      I have folded some test output changes in `TEST="T12529 T12921 mc13
      mc14"` into this patch that were not in the original.
    a49f95c2
all.T 21.2 KB