Details
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Type:
Bug
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Status: CLOSED
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Priority:
Major
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Resolution: Fixed
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Affects Version/s: None
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Fix Version/s: Scala 2.10.0-M3
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Component/s: Optimizer
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Labels:
Description
There appears to be a problem with InlineExceptionHandlers.
I noticed after compiling the compiler with -target:jvm-1.6 -optimize
as of https://github.com/scala/scala/commit/446de86b3e51f45418cc87c0c9ec43c30bbab3d4
and later trying to run with the usual VM options that activate the new verifier:
java -Xverify:all -XX:+UseSplitVerifier -XX:-FailOverToOldVerifier
There is some mismatch between stack map frames as emitted vs as computed by the verifier:
Exception in thread "main" java.lang.VerifyError:
|
Bad type on operand stack in method
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scala.reflect.internal.BaseTypeSeqs$BaseTypeSeq.liftedTree1$1(ILscala/reflect/internal/Types$RefinedType;)Lscala/reflect/internal/Types$Type;
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at offset 259
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at scala.reflect.internal.BaseTypeSeqs$class.newBaseTypeSeq(BaseTypeSeqs.scala:33)
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at scala.reflect.internal.SymbolTable.newBaseTypeSeq(SymbolTable.scala:13)
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at scala.reflect.internal.BaseTypeSeqs$class.$init$(BaseTypeSeqs.scala:176)
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at scala.reflect.internal.SymbolTable.<init>(SymbolTable.scala:13)
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at scala.tools.nsc.symtab.SymbolTable.<init>(SymbolTable.scala:9)
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at scala.tools.nsc.Global.<init>(Global.scala:34)
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at scala.tools.nsc.Global$.apply(Global.scala:1625)
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at scala.tools.nsc.Main$.newCompiler(Main.scala:76)
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at scala.tools.nsc.Driver.process(Driver.scala:45)
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at scala.tools.nsc.Driver.main(Driver.scala:65)
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at scala.tools.nsc.Main.main(Main.scala)
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The problem does not surface when the compiler is compiled with
-Yinline -Yclosure-elim -Ydead-code
There are two candidate culprits:
- GenASM, which delegates to ASM the computation of stack-maps, but computes some input for that: inameToSymbol(), getCommonSuperClass().
- InlineExceptionHandlers
GenASM seems not to be the culprit because inameToSymbol() doesn't run at all (rather, getCommonSuperClass() always hits the reverseJavaName cache). And if getCommonSuperClass() had a bug, we would have noticed already.
First I tried diagnosing with ASM's CheckClassAdapter , http://asm.ow2.org/doc/faq.html#Q4 , but it finds no error.
Thus we're left with javap -c -private -verbose , which does show a difference for the method in question:
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version 1: compiled with -optimize |
private final scala.reflect.internal.Types$Type liftedTree1$1(int, scala.reflect.internal.Types$RefinedType);
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Code:
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Stack=5, Locals=7, Args_size=3
|
0: aload_0
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1: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
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4: aload_2
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5: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
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8: iconst_m1
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9: aload_0
|
10: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
|
13: aload_2
|
14: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
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17: invokeinterface #381, 2; //InterfaceMethod scala/reflect/internal/Types.lubDepth:(Lscala/collection/immutable/List;)I
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22: invokeinterface #385, 4; //InterfaceMethod scala/reflect/internal/Types.mergePrefixAndArgs:(Lscala/collection/immutable/List;II)Lscala/Option;
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27: astore 5
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29: aload 5
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31: instanceof #387; //class scala/Some
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34: ifeq 86
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37: aload 5
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39: checkcast #387; //class scala/Some
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42: astore_3
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43: aload_3
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44: ifnull 86
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47: aload_0
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48: invokespecial #47; //Method pending:()Lscala/collection/mutable/BitSet;
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51: iload_1
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52: invokestatic #393; //Method scala/runtime/BoxesRunTime.boxToInteger:(I)Ljava/lang/Integer;
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55: iconst_0
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56: invokeinterface #399, 3; //InterfaceMethod scala/collection/mutable/SetLike.update:(Ljava/lang/Object;Z)V
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61: aload_0
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62: invokevirtual #40; //Method scala$reflect$internal$BaseTypeSeqs$$elems:()[Lscala/reflect/internal/Types$Type;
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65: iload_1
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66: aload_3
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67: invokevirtual #402; //Method scala/Some.x:()Ljava/lang/Object;
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70: checkcast #84; //class scala/reflect/internal/Types$Type
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73: aastore
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74: aload_3
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75: invokevirtual #402; //Method scala/Some.x:()Ljava/lang/Object;
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78: checkcast #84; //class scala/reflect/internal/Types$Type
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81: astore 4
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83: aload 4
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85: areturn
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86: getstatic #407; //Field scala/None$.MODULE$:Lscala/None$;
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89: dup
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90: ifnonnull 102
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93: pop
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94: aload 5
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96: ifnull 110
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99: goto 156
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102: aload 5
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104: invokevirtual #411; //Method java/lang/Object.equals:(Ljava/lang/Object;)Z
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107: ifeq 156
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110: aload_0
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111: new #349; //class scala/collection/mutable/StringBuilder
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114: dup
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115: invokespecial #351; //Method scala/collection/mutable/StringBuilder."<init>":()V
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118: ldc_w #413; //String no common type instance of base types
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121: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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124: aload_2
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125: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
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128: ldc_w #415; //String , and
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131: invokeinterface #362, 2; //InterfaceMethod scala/collection/TraversableOnce.mkString:(Ljava/lang/String;)Ljava/lang/String;
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136: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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139: ldc_w #417; //String exists.
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142: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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145: invokevirtual #368; //Method scala/collection/mutable/StringBuilder.toString:()Ljava/lang/String;
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148: invokespecial #419; //Method typeError:(Ljava/lang/String;)Lscala/runtime/Nothing$;
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151: astore 6
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153: goto 167
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156: new #421; //class scala/MatchError
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159: dup
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160: aload 5
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162: invokespecial #424; //Method scala/MatchError."<init>":(Ljava/lang/Object;)V
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165: astore 6
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167: aload_0
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168: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
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171: invokeinterface #69, 1; //InterfaceMethod scala/reflect/internal/BaseTypeSeqs.CyclicInheritance:()Ljava/lang/Throwable;
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176: dup
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177: ifnull 198
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180: goto 207
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183: astore 6
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185: aload_0
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186: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
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189: invokeinterface #69, 1; //InterfaceMethod scala/reflect/internal/BaseTypeSeqs.CyclicInheritance:()Ljava/lang/Throwable;
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194: dup
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195: ifnonnull 207
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198: pop
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199: aload 6
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201: ifnull 215
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204: goto 257
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207: aload 6
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209: invokevirtual #411; //Method java/lang/Object.equals:(Ljava/lang/Object;)Z
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212: ifeq 257
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215: aload_0
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216: new #349; //class scala/collection/mutable/StringBuilder
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219: dup
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220: invokespecial #351; //Method scala/collection/mutable/StringBuilder."<init>":()V
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223: ldc_w #426; //String computing the common type instance of base types
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226: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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229: aload_2
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230: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
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233: ldc_w #415; //String , and
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236: invokeinterface #362, 2; //InterfaceMethod scala/collection/TraversableOnce.mkString:(Ljava/lang/String;)Ljava/lang/String;
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241: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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244: ldc_w #428; //String leads to a cycle.
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247: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
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250: invokevirtual #368; //Method scala/collection/mutable/StringBuilder.toString:()Ljava/lang/String;
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253: invokespecial #419; //Method typeError:(Ljava/lang/String;)Lscala/runtime/Nothing$;
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256: athrow
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257: aload 6
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259: athrow
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Exception table:
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from to target type
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86 167 183 any
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0 85 183 any
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LocalVariableTable:
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Start Length Slot Name Signature
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0 260 0 this Lscala/reflect/internal/BaseTypeSeqs$BaseTypeSeq;
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0 260 1 i$1 I
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0 260 2 x2$1 Lscala/reflect/internal/Types$RefinedType;
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43 217 3 x2 Lscala/Some;
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|
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LineNumberTable:
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line 66: 0
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line 59: 4
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line 66: 8
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line 59: 13
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line 66: 17
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line 67: 29
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line 68: 47
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line 69: 61
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line 66: 66
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line 69: 73
|
line 66: 74
|
line 67: 81
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line 66: 83
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line 65: 85
|
line 71: 86
|
line 72: 110
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line 73: 111
|
line 59: 124
|
line 73: 128
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line 72: 148
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line 66: 156
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line 76: 167
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line 65: 167
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line 65: 183
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line 76: 185
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line 77: 215
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line 78: 216
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line 59: 229
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line 78: 233
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line 77: 253
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line 65: 257
|
|
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StackMapTable: number_of_entries = 10
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frame_type = 254 /* append */
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offset_delta = 86
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locals = [ bogus, bogus, class scala/Option ]
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frame_type = 79 /* same_locals_1_stack_item */
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stack = [ class scala/None$ ]
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frame_type = 7 /* same */
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frame_type = 45 /* same */
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frame_type = 252 /* append */
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offset_delta = 10
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locals = [ class java/lang/Object ]
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frame_type = 255 /* full_frame */
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offset_delta = 15
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locals = [ class scala/reflect/internal/BaseTypeSeqs$BaseTypeSeq, int, class scala/reflect/internal/Types$RefinedType ]
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stack = [ class java/lang/Throwable ]
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frame_type = 255 /* full_frame */
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offset_delta = 14
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locals = [ class scala/reflect/internal/BaseTypeSeqs$BaseTypeSeq, int, class scala/reflect/internal/Types$RefinedType, bogus, bogus, bogus, class java/lang/Object ]
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stack = [ class java/lang/Throwable ]
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frame_type = 72 /* same_locals_1_stack_item */
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stack = [ class java/lang/Throwable ]
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frame_type = 7 /* same */
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frame_type = 41 /* same */
|
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version 2: compiled with -Yinline -Yclosure-elim -Ydead-code |
private final scala.reflect.internal.Types$Type liftedTree1$1(int, scala.reflect.internal.Types$RefinedType);
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Code:
|
Stack=5, Locals=7, Args_size=3
|
0: aload_0
|
1: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
|
4: aload_2
|
5: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
|
8: iconst_m1
|
9: aload_0
|
10: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
|
13: aload_2
|
14: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
|
17: invokeinterface #381, 2; //InterfaceMethod scala/reflect/internal/Types.lubDepth:(Lscala/collection/immutable/List;)I
|
22: invokeinterface #385, 4; //InterfaceMethod scala/reflect/internal/Types.mergePrefixAndArgs:(Lscala/collection/immutable/List;II)Lscala/Option;
|
27: astore 5
|
29: aload 5
|
31: instanceof #387; //class scala/Some
|
34: ifeq 86
|
37: aload 5
|
39: checkcast #387; //class scala/Some
|
42: astore_3
|
43: aload_3
|
44: ifnull 86
|
47: aload_0
|
48: invokespecial #47; //Method pending:()Lscala/collection/mutable/BitSet;
|
51: iload_1
|
52: invokestatic #393; //Method scala/runtime/BoxesRunTime.boxToInteger:(I)Ljava/lang/Integer;
|
55: iconst_0
|
56: invokeinterface #399, 3; //InterfaceMethod scala/collection/mutable/SetLike.update:(Ljava/lang/Object;Z)V
|
61: aload_0
|
62: invokevirtual #40; //Method scala$reflect$internal$BaseTypeSeqs$$elems:()[Lscala/reflect/internal/Types$Type;
|
65: iload_1
|
66: aload_3
|
67: invokevirtual #402; //Method scala/Some.x:()Ljava/lang/Object;
|
70: checkcast #84; //class scala/reflect/internal/Types$Type
|
73: aastore
|
74: aload_3
|
75: invokevirtual #402; //Method scala/Some.x:()Ljava/lang/Object;
|
78: checkcast #84; //class scala/reflect/internal/Types$Type
|
81: astore 4
|
83: aload 4
|
85: areturn
|
86: getstatic #407; //Field scala/None$.MODULE$:Lscala/None$;
|
89: dup
|
90: ifnonnull 102
|
93: pop
|
94: aload 5
|
96: ifnull 110
|
99: goto 152
|
102: aload 5
|
104: invokevirtual #411; //Method java/lang/Object.equals:(Ljava/lang/Object;)Z
|
107: ifeq 152
|
110: aload_0
|
111: new #349; //class scala/collection/mutable/StringBuilder
|
114: dup
|
115: invokespecial #351; //Method scala/collection/mutable/StringBuilder."<init>":()V
|
118: ldc_w #413; //String no common type instance of base types
|
121: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
124: aload_2
|
125: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
|
128: ldc_w #415; //String , and
|
131: invokeinterface #362, 2; //InterfaceMethod scala/collection/TraversableOnce.mkString:(Ljava/lang/String;)Ljava/lang/String;
|
136: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
139: ldc_w #417; //String exists.
|
142: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
145: invokevirtual #368; //Method scala/collection/mutable/StringBuilder.toString:()Ljava/lang/String;
|
148: invokespecial #419; //Method typeError:(Ljava/lang/String;)Lscala/runtime/Nothing$;
|
151: athrow
|
152: new #421; //class scala/MatchError
|
155: dup
|
156: aload 5
|
158: invokespecial #424; //Method scala/MatchError."<init>":(Ljava/lang/Object;)V
|
161: athrow
|
162: astore 6
|
164: aload_0
|
165: invokevirtual #63; //Method scala$reflect$internal$BaseTypeSeqs$BaseTypeSeq$$$outer:()Lscala/reflect/internal/SymbolTable;
|
168: invokeinterface #69, 1; //InterfaceMethod scala/reflect/internal/BaseTypeSeqs.CyclicInheritance:()Ljava/lang/Throwable;
|
173: dup
|
174: ifnonnull 186
|
177: pop
|
178: aload 6
|
180: ifnull 194
|
183: goto 236
|
186: aload 6
|
188: invokevirtual #411; //Method java/lang/Object.equals:(Ljava/lang/Object;)Z
|
191: ifeq 236
|
194: aload_0
|
195: new #349; //class scala/collection/mutable/StringBuilder
|
198: dup
|
199: invokespecial #351; //Method scala/collection/mutable/StringBuilder."<init>":()V
|
202: ldc_w #426; //String computing the common type instance of base types
|
205: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
208: aload_2
|
209: invokevirtual #91; //Method scala/reflect/internal/Types$RefinedType.parents:()Lscala/collection/immutable/List;
|
212: ldc_w #415; //String , and
|
215: invokeinterface #362, 2; //InterfaceMethod scala/collection/TraversableOnce.mkString:(Ljava/lang/String;)Ljava/lang/String;
|
220: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
223: ldc_w #428; //String leads to a cycle.
|
226: invokevirtual #357; //Method scala/collection/mutable/StringBuilder.append:(Ljava/lang/Object;)Lscala/collection/mutable/StringBuilder;
|
229: invokevirtual #368; //Method scala/collection/mutable/StringBuilder.toString:()Ljava/lang/String;
|
232: invokespecial #419; //Method typeError:(Ljava/lang/String;)Lscala/runtime/Nothing$;
|
235: athrow
|
236: aload 6
|
238: athrow
|
Exception table:
|
from to target type
|
86 162 162 any
|
0 85 162 any
|
LocalVariableTable:
|
Start Length Slot Name Signature
|
0 239 0 this Lscala/reflect/internal/BaseTypeSeqs$BaseTypeSeq;
|
0 239 1 i$1 I
|
0 239 2 x2$1 Lscala/reflect/internal/Types$RefinedType;
|
43 196 3 x2 Lscala/Some;
|
|
|
LineNumberTable:
|
line 66: 0
|
line 59: 4
|
line 66: 8
|
line 59: 13
|
line 66: 17
|
line 67: 29
|
line 68: 47
|
line 69: 61
|
line 66: 66
|
line 69: 73
|
line 66: 74
|
line 67: 81
|
line 66: 83
|
line 65: 85
|
line 71: 86
|
line 72: 110
|
line 73: 111
|
line 59: 124
|
line 73: 128
|
line 72: 148
|
line 66: 152
|
line 65: 162
|
line 76: 164
|
line 77: 194
|
line 78: 195
|
line 59: 208
|
line 78: 212
|
line 77: 232
|
line 65: 236
|
|
|
StackMapTable: number_of_entries = 8
|
frame_type = 254 /* append */
|
offset_delta = 86
|
locals = [ bogus, bogus, class scala/Option ]
|
frame_type = 79 /* same_locals_1_stack_item */
|
stack = [ class scala/None$ ]
|
frame_type = 7 /* same */
|
frame_type = 41 /* same */
|
frame_type = 255 /* full_frame */
|
offset_delta = 9
|
locals = [ class scala/reflect/internal/BaseTypeSeqs$BaseTypeSeq, int, class scala/reflect/internal/Types$RefinedType ]
|
stack = [ class java/lang/Throwable ]
|
frame_type = 255 /* full_frame */
|
offset_delta = 23
|
locals = [ class scala/reflect/internal/BaseTypeSeqs$BaseTypeSeq, int, class scala/reflect/internal/Types$RefinedType, bogus, bogus, bogus, class java/lang/Throwable ]
|
stack = [ class java/lang/Throwable ]
|
frame_type = 7 /* same */
|
frame_type = 41 /* same */
|
A question we could ask ourselves is: What performance gain (if any) does InlineExceptionHandlers buy us?
If negative, null, or negligible, then, shouldn't we consider removing InlineExceptionHandlers from the pipeline? This question is unrelated to this bug but becomes more pressing because of it.
Given that the build optimizes library and compiler, this bug means our build can't target 1.6 classfiles.