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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2015-12-04 12:08:37 +0000 |
|---|---|---|
| committer | Simon Peyton Jones <simonpj@microsoft.com> | 2015-12-04 14:21:32 +0000 |
| commit | 1160dc516f8b27249d819665883409ee270a743f (patch) | |
| tree | ad74db7f08839cbfb315e18dada1c416ad6d0dcb /testsuite/tests | |
| parent | 822141b95174f068872fd4e491da764139ce626f (diff) | |
| download | haskell-1160dc516f8b27249d819665883409ee270a743f.tar.gz | |
Fix egregious error in eta-reduction of data families
This terrible and long-standing bug was shown up by Trac #11148.
We are trying to eta-reduce a data family instance, so that we
can then derive Functor or Generic. But we were assuming, for
absolutely not reason whatsoever, that the type variables were
lined up in a convenient order. The fact that it ever worked
was a fluke.
This patch fixes it properly. Main change is in eta_reduce
in TcInstDcls.tcDataFamInstDecl
Diffstat (limited to 'testsuite/tests')
| -rw-r--r-- | testsuite/tests/deriving/should_compile/Makefile | 10 | ||||
| -rw-r--r-- | testsuite/tests/deriving/should_compile/T11148.hs | 11 | ||||
| -rw-r--r-- | testsuite/tests/deriving/should_compile/all.T | 2 |
3 files changed, 22 insertions, 1 deletions
diff --git a/testsuite/tests/deriving/should_compile/Makefile b/testsuite/tests/deriving/should_compile/Makefile index f9e816f13f..581aabbce0 100644 --- a/testsuite/tests/deriving/should_compile/Makefile +++ b/testsuite/tests/deriving/should_compile/Makefile @@ -2,7 +2,15 @@ TOP=../../.. include $(TOP)/mk/boilerplate.mk include $(TOP)/mk/test.mk -.PHONY: T1133 +.PHONY: T1133 T11148 + +T11148: + $(RM) T11148.hi T11148.o + '$(TEST_HC)' $(TEST_HC_OPTS) -c -dunique-increment=-1 T11148.hs + # Set the unique-increment to '-1' to trigger the bug + # This has to be done on the command line; + # an OPTIONS_GHC pragma does not do it + T1133: '$(TEST_HC)' $(TEST_HC_OPTS) -c T1133.hs-boot '$(TEST_HC)' $(TEST_HC_OPTS) -c T1133a.hs diff --git a/testsuite/tests/deriving/should_compile/T11148.hs b/testsuite/tests/deriving/should_compile/T11148.hs new file mode 100644 index 0000000000..5e505beb31 --- /dev/null +++ b/testsuite/tests/deriving/should_compile/T11148.hs @@ -0,0 +1,11 @@ +{-# LANGUAGE TypeFamilies #-} +{-# LANGUAGE DeriveFunctor #-} +{-# LANGUAGE FlexibleInstances #-} + +module T11148 where + +data family G a b c d +data instance G Int b Float d = G deriving Functor + +data family H a b c d +data instance H [b] b d c = H deriving Functor diff --git a/testsuite/tests/deriving/should_compile/all.T b/testsuite/tests/deriving/should_compile/all.T index 9ffa07df3d..ac41df4a39 100644 --- a/testsuite/tests/deriving/should_compile/all.T +++ b/testsuite/tests/deriving/should_compile/all.T @@ -56,3 +56,5 @@ test('T4896', normal, compile, ['']) test('T7947', extra_clean(['T7947a.o', 'T7947a.hi', 'T7947b.o', 'T7947b.hi']), multimod_compile, ['T7947', '-v0']) test('T10561', normal, compile_fail, ['']) test('T10487', extra_clean(['T10487_M.o', 'T10487_M.hi']), multimod_compile, ['T10487', '-v0']) +test('T11148', normal, run_command, + ['$MAKE -s --no-print-directory T11148']) |