| | 12 | |
| | 13 | == Frequently reported bugs == |
| | 14 | |
| | 15 | GHC 7.4 gives an internal error (panic) on: |
| | 16 | |
| | 17 | * Lowercase identifier used in a deriving clause, such as {{{data A = B deriving show}}}. Use uppercase: {{{deriving Show}}}. Bug #5961. |
| | 18 | * Invalid instances: {{{instance A => B => C where ...}}}, {{{instance A -> B}}}, {{{instance (A, B)}}} etc. Bug #5951. |
| | 19 | |
| | 20 | Both errors are fixed in GHC 7.6, if possible, you should upgrade. |
| | 21 | |
| | 22 | GHC 7.6 gives a panic on an invalid strictness annotation {{{data X = X (!Maybe Int)}}}. The correct way is {{{data X = X (!(Maybe Int))}}}. This is fixed in the development version. See bug #7210. |
