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freakboy3742/Stack trace

Created August 18, 2016 14:04
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VerifyError?
Raw
javap output
Classfile /Users/rkm/projects/beeware/voc/freakboy3742/local/python/example/__init__.class
Last modified 18/08/2016; size 1800 bytes
MD5 checksum e44b3a6ceba29f2b73e0357a7b40f7ed
Compiled from "example.py"
public class python.example.__init__ extends org.python.types.Module
SourceFile: "example.py"
minor version: 0
major version: 50
flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
#1 = Class #2 // python/example/__init__
#2 = Utf8 python/example/__init__
#3 = Class #4 // org/python/types/Module
#4 = Utf8 org/python/types/Module
#5 = Utf8 module$import
#6 = Utf8 ()V
#7 = Utf8 Code
#8 = Class #9 // org/python/types/List
#9 = Utf8 org/python/types/List
#10 = Class #11 // java/util/ArrayList
#11 = Utf8 java/util/ArrayList
#12 = Methodref #10.#13 // java/util/ArrayList."<init>":(I)V
#13 = NameAndType #14:#15 // "<init>":(I)V
#14 = Utf8 <init>
#15 = Utf8 (I)V
#16 = Class #17 // org/python/types/Int
#17 = Utf8 org/python/types/Int
#18 = Methodref #16.#19 // org/python/types/Int."<init>":(J)V
#19 = NameAndType #14:#20 // "<init>":(J)V
#20 = Utf8 (J)V
#21 = InterfaceMethodref #22.#24 // java/util/List.add:(Ljava/lang/Object;)Z
#22 = Class #23 // java/util/List
#23 = Utf8 java/util/List
#24 = NameAndType #25:#26 // add:(Ljava/lang/Object;)Z
#25 = Utf8 add
#26 = Utf8 (Ljava/lang/Object;)Z
#27 = Long 2l
#29 = Methodref #8.#30 // org/python/types/List."<init>":(Ljava/util/List;)V
#30 = NameAndType #14:#31 // "<init>":(Ljava/util/List;)V
#31 = Utf8 (Ljava/util/List;)V
#32 = Fieldref #33.#35 // python/sys/__init__.modules:Lorg/python/types/Dict;
#33 = Class #34 // python/sys/__init__
#34 = Utf8 python/sys/__init__
#35 = NameAndType #36:#37 // modules:Lorg/python/types/Dict;
#36 = Utf8 modules
#37 = Utf8 Lorg/python/types/Dict;
#38 = Class #39 // org/python/types/Str
#39 = Utf8 org/python/types/Str
#40 = String #41 // example
#41 = Utf8 example
#42 = Methodref #38.#43 // org/python/types/Str."<init>":(Ljava/lang/String;)V
#43 = NameAndType #14:#44 // "<init>":(Ljava/lang/String;)V
#44 = Utf8 (Ljava/lang/String;)V
#45 = InterfaceMethodref #46.#48 // org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
#46 = Class #47 // org/python/Object
#47 = Utf8 org/python/Object
#48 = NameAndType #49:#50 // __getitem__:(Lorg/python/Object;)Lorg/python/Object;
#49 = Utf8 __getitem__
#50 = Utf8 (Lorg/python/Object;)Lorg/python/Object;
#51 = String #52 // x
#52 = Utf8 x
#53 = InterfaceMethodref #46.#54 // org/python/Object.__setattr__:(Ljava/lang/String;Lorg/python/Object;)V
#54 = NameAndType #55:#56 // __setattr__:(Ljava/lang/String;Lorg/python/Object;)V
#55 = Utf8 __setattr__
#56 = Utf8 (Ljava/lang/String;Lorg/python/Object;)V
#57 = Methodref #8.#58 // org/python/types/List."<init>":()V
#58 = NameAndType #14:#6 // "<init>":()V
#59 = InterfaceMethodref #46.#60 // org/python/Object.__getattribute__:(Ljava/lang/String;)Lorg/python/Object;
#60 = NameAndType #61:#62 // __getattribute__:(Ljava/lang/String;)Lorg/python/Object;
#61 = Utf8 __getattribute__
#62 = Utf8 (Ljava/lang/String;)Lorg/python/Object;
#63 = InterfaceMethodref #46.#64 // org/python/Object.__iter__:()Lorg/python/Iterable;
#64 = NameAndType #65:#66 // __iter__:()Lorg/python/Iterable;
#65 = Utf8 __iter__
#66 = Utf8 ()Lorg/python/Iterable;
#67 = Class #68 // org/python/Iterable
#68 = Utf8 org/python/Iterable
#69 = InterfaceMethodref #67.#70 // org/python/Iterable.__next__:()Lorg/python/Object;
#70 = NameAndType #71:#72 // __next__:()Lorg/python/Object;
#71 = Utf8 __next__
#72 = Utf8 ()Lorg/python/Object;
#73 = String #74 // v
#74 = Utf8 v
#75 = Methodref #8.#76 // org/python/types/List.append:(Lorg/python/Object;)Lorg/python/Object;
#76 = NameAndType #77:#50 // append:(Lorg/python/Object;)Lorg/python/Object;
#77 = Utf8 append
#78 = Class #79 // java/util/HashMap
#79 = Utf8 java/util/HashMap
#80 = Methodref #78.#58 // java/util/HashMap."<init>":()V
#81 = String #82 // print
#82 = Utf8 print
#83 = Class #84 // org/python/Callable
#84 = Utf8 org/python/Callable
#85 = InterfaceMethodref #83.#86 // org/python/Callable.invoke:([Lorg/python/Object;Ljava/util/Map;)Lorg/python/Object;
#86 = NameAndType #87:#88 // invoke:([Lorg/python/Object;Ljava/util/Map;)Lorg/python/Object;
#87 = Utf8 invoke
#88 = Utf8 ([Lorg/python/Object;Ljava/util/Map;)Lorg/python/Object;
#89 = Utf8 LineNumberTable
#90 = Class #91 // org/python/exceptions/StopIteration
#91 = Utf8 org/python/exceptions/StopIteration
#92 = Methodref #3.#58 // org/python/types/Module."<init>":()V
#93 = Utf8 main
#94 = Utf8 ([Ljava/lang/String;)V
#95 = Methodref #1.#58 // python/example/__init__."<init>":()V
#96 = InterfaceMethodref #46.#97 // org/python/Object.__setitem__:(Lorg/python/Object;Lorg/python/Object;)V
#97 = NameAndType #98:#99 // __setitem__:(Lorg/python/Object;Lorg/python/Object;)V
#98 = Utf8 __setitem__
#99 = Utf8 (Lorg/python/Object;Lorg/python/Object;)V
#100 = String #101 // __main__
#101 = Utf8 __main__
#102 = Methodref #1.#103 // python/example/__init__.module$import:()V
#103 = NameAndType #5:#6 // module$import:()V
#104 = Fieldref #105.#107 // org/python/exceptions/SystemExit.return_code:I
#105 = Class #106 // org/python/exceptions/SystemExit
#106 = Utf8 org/python/exceptions/SystemExit
#107 = NameAndType #108:#109 // return_code:I
#108 = Utf8 return_code
#109 = Utf8 I
#110 = Methodref #111.#113 // java/lang/System.exit:(I)V
#111 = Class #112 // java/lang/System
#112 = Utf8 java/lang/System
#113 = NameAndType #114:#15 // exit:(I)V
#114 = Utf8 exit
#115 = Utf8 SourceFile
#116 = Utf8 example.py
{
public void module$import();
Signature: ()V
flags: ACC_PUBLIC
LineNumberTable:
line 1: 9
line 2: 87
Code:
stack=15, locals=5, args_size=1
0: aconst_null
1: astore_1
2: aconst_null
3: astore_2
4: aconst_null
5: astore_3
6: aconst_null
7: astore 4
9: new #8 // class org/python/types/List
12: dup
13: new #10 // class java/util/ArrayList
16: dup
17: iconst_2
18: invokespecial #12 // Method java/util/ArrayList."<init>":(I)V
21: dup
22: new #16 // class org/python/types/Int
25: dup
26: lconst_1
27: invokespecial #18 // Method org/python/types/Int."<init>":(J)V
30: invokeinterface #21, 2 // InterfaceMethod java/util/List.add:(Ljava/lang/Object;)Z
35: pop
36: dup
37: new #16 // class org/python/types/Int
40: dup
41: ldc2_w #27 // long 2l
44: invokespecial #18 // Method org/python/types/Int."<init>":(J)V
47: invokeinterface #21, 2 // InterfaceMethod java/util/List.add:(Ljava/lang/Object;)Z
52: pop
53: invokespecial #29 // Method org/python/types/List."<init>":(Ljava/util/List;)V
56: astore_1
57: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
60: new #38 // class org/python/types/Str
63: dup
64: ldc_w #40 // String example
67: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
70: invokeinterface #45, 2 // InterfaceMethod org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
75: checkcast #3 // class org/python/types/Module
78: ldc_w #51 // String x
81: aload_1
82: invokeinterface #53, 3 // InterfaceMethod org/python/Object.__setattr__:(Ljava/lang/String;Lorg/python/Object;)V
87: iconst_1
88: anewarray #46 // class org/python/Object
91: astore_1
92: new #8 // class org/python/types/List
95: dup
96: invokespecial #57 // Method org/python/types/List."<init>":()V
99: astore_2
100: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
103: new #38 // class org/python/types/Str
106: dup
107: ldc_w #40 // String example
110: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
113: invokeinterface #45, 2 // InterfaceMethod org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
118: checkcast #3 // class org/python/types/Module
121: ldc_w #51 // String x
124: invokeinterface #59, 2 // InterfaceMethod org/python/Object.__getattribute__:(Ljava/lang/String;)Lorg/python/Object;
129: invokeinterface #63, 1 // InterfaceMethod org/python/Object.__iter__:()Lorg/python/Iterable;
134: astore_3
135: aload_3
136: checkcast #67 // class org/python/Iterable
139: invokeinterface #69, 1 // InterfaceMethod org/python/Iterable.__next__:()Lorg/python/Object;
144: goto 151
147: pop
148: goto 222
151: astore 4
153: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
156: new #38 // class org/python/types/Str
159: dup
160: ldc_w #40 // String example
163: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
166: invokeinterface #45, 2 // InterfaceMethod org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
171: checkcast #3 // class org/python/types/Module
174: ldc_w #73 // String v
177: aload 4
179: invokeinterface #53, 3 // InterfaceMethod org/python/Object.__setattr__:(Ljava/lang/String;Lorg/python/Object;)V
184: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
187: new #38 // class org/python/types/Str
190: dup
191: ldc_w #40 // String example
194: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
197: invokeinterface #45, 2 // InterfaceMethod org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
202: checkcast #3 // class org/python/types/Module
205: ldc_w #73 // String v
208: invokeinterface #59, 2 // InterfaceMethod org/python/Object.__getattribute__:(Ljava/lang/String;)Lorg/python/Object;
213: aload_2
214: swap
215: invokespecial #75 // Method org/python/types/List.append:(Lorg/python/Object;)Lorg/python/Object;
218: pop
219: goto 135
222: aload_2
223: aload_1
224: swap
225: iconst_0
226: swap
227: aastore
228: new #78 // class java/util/HashMap
231: dup
232: invokespecial #80 // Method java/util/HashMap."<init>":()V
235: astore_3
236: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
239: new #38 // class org/python/types/Str
242: dup
243: ldc_w #40 // String example
246: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
249: invokeinterface #45, 2 // InterfaceMethod org/python/Object.__getitem__:(Lorg/python/Object;)Lorg/python/Object;
254: checkcast #3 // class org/python/types/Module
257: ldc_w #81 // String print
260: invokeinterface #59, 2 // InterfaceMethod org/python/Object.__getattribute__:(Ljava/lang/String;)Lorg/python/Object;
265: checkcast #83 // class org/python/Callable
268: aload_1
269: aload_3
270: invokeinterface #85, 3 // InterfaceMethod org/python/Callable.invoke:([Lorg/python/Object;Ljava/util/Map;)Lorg/python/Object;
275: pop
276: return
Exception table:
from to target type
135 144 147 Class org/python/exceptions/StopIteration
LineNumberTable:
line 1: 9
line 2: 87
public python.example.__init__();
Signature: ()V
flags: ACC_PUBLIC
Code:
stack=2, locals=1, args_size=1
0: aload_0
1: dup
2: invokespecial #92 // Method org/python/types/Module."<init>":()V
5: return
public static void main(java.lang.String[]);
Signature: ([Ljava/lang/String;)V
flags: ACC_PUBLIC, ACC_STATIC
LineNumberTable:
Code:
stack=8, locals=2, args_size=1
0: aconst_null
1: astore_1
2: getstatic #32 // Field python/sys/__init__.modules:Lorg/python/types/Dict;
5: dup
6: new #38 // class org/python/types/Str
9: dup
10: ldc_w #40 // String example
13: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
16: new #1 // class python/example/__init__
19: dup
20: dup
21: invokespecial #95 // Method "<init>":()V
24: astore_1
25: invokeinterface #96, 3 // InterfaceMethod org/python/Object.__setitem__:(Lorg/python/Object;Lorg/python/Object;)V
30: new #38 // class org/python/types/Str
33: dup
34: ldc_w #100 // String __main__
37: invokespecial #42 // Method org/python/types/Str."<init>":(Ljava/lang/String;)V
40: aload_1
41: invokeinterface #96, 3 // InterfaceMethod org/python/Object.__setitem__:(Lorg/python/Object;Lorg/python/Object;)V
46: aload_1
47: invokevirtual #102 // Method module$import:()V
50: goto 59
53: getfield #104 // Field org/python/exceptions/SystemExit.return_code:I
56: invokestatic #110 // Method java/lang/System.exit:(I)V
59: return
Exception table:
from to target type
2 50 53 Class org/python/exceptions/SystemExit
LineNumberTable:
}
Raw
Stack trace
Exception in thread "main" java.lang.VerifyError: Expecting a stackmap frame at branch target 53
Exception Details:
Location:
python/example/__init__.main([Ljava/lang/String;)V @2: getstatic
Reason:
Expected stackmap frame at this location.
Bytecode:
0000000: 014c b200 2059 bb00 2659 1300 28b7 002a
0000010: bb00 0159 59b7 005f 4cb9 0060 0300 bb00
0000020: 2659 1300 64b7 002a 2bb9 0060 0300 2bb6
0000030: 0066 a700 09b4 0068 b800 6eb1
Exception Handler Table:
bci [2, 50] => handler: 53
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2570)
at java.lang.Class.getMethod0(Class.java:2813)
at java.lang.Class.getMethod(Class.java:1663)
at sun.launcher.LauncherHelper.getMainMethod(LauncherHelper.java:494)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:486)
@freakboy3742
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freakboy3742 commented Aug 18, 2016 •
edited
Loading

The class file whose dump is shown in the first file sample throws the given stack trace. However, for the life of me, I can't work out why.

The class file has been generated as bytecode, so there is no original Java source file. I'm used to seeing VerifyErrors when offsets don't line up, but in this case, they all look fine to me.

I've tried using the ObjectWeb class verification tool - it doesn't report any problems.

If it helps, you can download the original class file (python/example/__init__.class)

This class file depends on a support JAR file.

@freakboy3742
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Problem resolved - it was this line. It should be invokevirtual not invokespecial; if you turn off verification, it still works, but for some reason, it manifests as a completely unhelpful verification error.

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