Add a test for -fdisambiguate-record-fields (trac #1401)

testsuite/tests/ghc-regress/rename/should_compile/Rn059_A.hs

+
+module Rn059_A where
+
+data A = A { label :: Char }
+

testsuite/tests/ghc-regress/rename/should_compile/Rn059_B.hs

+
+module Rn059_B where
+
+data B = B { label :: Char }
+

testsuite/tests/ghc-regress/rename/should_compile/all.T

@@ -66,6 +66,8 @@ test('rn055', normal, compile, [''])
 test('rn056', normal, compile, [''])
 test('rn057', normal, compile, [''])
 test('rn058', normal, compile, [''])
+test('rn059', normal, multimod_compile, ['rn059', '-v0'])
+clean(['Rn059_A.hi', 'Rn059_A.o', 'Rn059_B.hi', 'Rn059_B.o'])
 
 test('timing001', normal, compile, [''])
 test('timing002', normal, compile, [''])

testsuite/tests/ghc-regress/rename/should_compile/rn059.hs

+{-# OPTIONS_GHC -fdisambiguate-record-fields #-}
+
+module Foo () where
+
+import Rn059_A
+import Rn059_B
+
+a = A { label = 'a' }
+
+b = B { label = 'b' }
+
+f (A { label = a }) (B { label = b }) = (a,b)
+