diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala | 17 | ||||
| -rw-r--r-- | test/files/neg/t6902.check | 10 | ||||
| -rw-r--r-- | test/files/neg/t6902.flags | 1 | ||||
| -rw-r--r-- | test/files/neg/t6902.scala | 23 | ||||
| -rw-r--r-- | test/files/run/t6011c.scala | 13 |
5 files changed, 55 insertions, 9 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala b/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala index fa8aff5cdd..9746b05c03 100644 --- a/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala +++ b/src/compiler/scala/tools/nsc/typechecker/PatternMatching.scala @@ -3225,6 +3225,7 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL // TODO: make more fine-grained, as we don't always need to jump def canJump: Boolean + /** Should exhaustivity analysis be skipped? */ def unchecked: Boolean @@ -3458,12 +3459,10 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL case Some(cds) => cds } - val allReachable = unchecked || { - // a switch with duplicate cases yields a verify error, - // and a switch with duplicate cases and guards cannot soundly be rewritten to an unguarded switch - // (even though the verify error would disappear, the behaviour would change) - unreachableCase(caseDefsWithGuards) map (cd => reportUnreachable(cd.body.pos)) isEmpty - } + // a switch with duplicate cases yields a verify error, + // and a switch with duplicate cases and guards cannot soundly be rewritten to an unguarded switch + // (even though the verify error would disappear, the behaviour would change) + val allReachable = unreachableCase(caseDefsWithGuards) map (cd => reportUnreachable(cd.body.pos)) isEmpty if (!allReachable) Nil else if (noGuards(caseDefsWithGuards)) { @@ -3710,10 +3709,10 @@ trait PatternMatching extends Transform with TypingTransformers with ast.TreeDSL with SymbolicMatchAnalysis with DPLLSolver { self: TreeMakers => override def optimizeCases(prevBinder: Symbol, cases: List[List[TreeMaker]], pt: Type, unchecked: Boolean): (List[List[TreeMaker]], List[Tree]) = { + unreachableCase(prevBinder, cases, pt) foreach { caseIndex => + reportUnreachable(cases(caseIndex).last.pos) + } if (!unchecked) { - unreachableCase(prevBinder, cases, pt) foreach { caseIndex => - reportUnreachable(cases(caseIndex).last.pos) - } val counterExamples = exhaustive(prevBinder, cases, pt) if (counterExamples.nonEmpty) reportMissingCases(prevBinder.pos, counterExamples) diff --git a/test/files/neg/t6902.check b/test/files/neg/t6902.check new file mode 100644 index 0000000000..8ad7fd37f9 --- /dev/null +++ b/test/files/neg/t6902.check @@ -0,0 +1,10 @@ +t6902.scala:4: error: unreachable code + case Some(b) => 3 // no warning was emitted + ^ +t6902.scala:9: error: unreachable code + case Some(b) => 3 // no warning was emitted + ^ +t6902.scala:21: error: unreachable code + case 1 => 3 // crash + ^ +three errors found diff --git a/test/files/neg/t6902.flags b/test/files/neg/t6902.flags new file mode 100644 index 0000000000..e8fb65d50c --- /dev/null +++ b/test/files/neg/t6902.flags @@ -0,0 +1 @@ +-Xfatal-warnings
\ No newline at end of file diff --git a/test/files/neg/t6902.scala b/test/files/neg/t6902.scala new file mode 100644 index 0000000000..ce5ff8b6fb --- /dev/null +++ b/test/files/neg/t6902.scala @@ -0,0 +1,23 @@ +object Test { + Some(Some(1)) collect { + case Some(a) => 2 + case Some(b) => 3 // no warning was emitted + } + + (Some(1): @ unchecked) match { + case Some(a) => 2 + case Some(b) => 3 // no warning was emitted + } + + // A variation of SI-6011, which eluded the fix + // in 2.10.0. + // + // duplicate keys in SWITCH, can't pick arbitrarily one of them to evict, see SI-6011. + // at scala.reflect.internal.SymbolTable.abort(SymbolTable.scala:50) + // at scala.tools.nsc.Global.abort(Global.scala:249) + // at scala.tools.nsc.backend.jvm.GenASM$JPlainBuilder$jcode$.emitSWITCH(GenASM.scala:1850) + ((1: Byte): @unchecked @annotation.switch) match { + case 1 => 2 + case 1 => 3 // crash + } +} diff --git a/test/files/run/t6011c.scala b/test/files/run/t6011c.scala new file mode 100644 index 0000000000..0647e3f81a --- /dev/null +++ b/test/files/run/t6011c.scala @@ -0,0 +1,13 @@ +object Test extends App { + // A variation of SI-6011, which eluded the fix + // in 2.10.0. + // + // duplicate keys in SWITCH, can't pick arbitrarily one of them to evict, see SI-6011. + // at scala.reflect.internal.SymbolTable.abort(SymbolTable.scala:50) + // at scala.tools.nsc.Global.abort(Global.scala:249) + // at scala.tools.nsc.backend.jvm.GenASM$JPlainBuilder$jcode$.emitSWITCH(GenASM.scala:1850) + ((1: Byte): @unchecked @annotation.switch) match { + case 1 => 2 + case 1 => 3 // crash + } +} |