JDK-8371472 : C2 compilation fails with "Error mixing types: vectory and int:0"
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 26
  • Priority: P3
  • Status: Closed
  • Resolution: Duplicate
  • Submitted: 2025-11-07
  • Updated: 2025-11-10
  • Resolved: 2025-11-07
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JDK 26
26Resolved
Related Reports
Causes :  
JDK-8369448 - C2 SuperWord: refactor VTransform to do move_unordered_reduction_out_of_loop during VTransform::optimize
Duplicate :  
JDK-8371065 - C2 SuperWord: VTransformLoopPhiNode::apply set wrong type, led to wrong constant folding of phi
Description
java -XX:CompileCommand=quiet -XX:CompileCommand=compileonly,Test::mainTest -XX:-TieredCompilation -Xbatch -XX:+StressIGVN -XX:RepeatCompilation=100 Test.java

Or with -XX:StressSeed=821213477 instead of RepeatCompilation

Error mixing types: vectory<I,8> and int:0

# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/workspace/open/src/hotspot/share/opto/type.cpp:1331), pid=715923, tid=715942
#  Error: ShouldNotReachHere()
#
# JRE version: Java(TM) SE Runtime Environment (26.0+21) (fastdebug build 26-ea+21-2147)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 26-ea+21-2147, mixed mode, sharing, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0x1b977d9]  Type::typerr(Type const*) const+0x79

Current CompileTask:
C2:16564    4   !b        Test::mainTest (750 bytes)

Stack: [0x000000ec90300000,0x000000ec90400000],  sp=0x000000ec903fb390,  free space=1004k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [jvm.dll+0x108afae]  Type::typerr+0x6e  (type.cpp:1331)
V  [jvm.dll+0x108f272]  TypeVect::xmeet+0x1b2  (type.cpp:2469)
V  [jvm.dll+0x1089b7f]  Type::meet_helper+0x2af  (type.cpp:1027)
V  [jvm.dll+0x273a3a]  AddNode::add_of_identity+0x8a  (addnode.cpp:240)
V  [jvm.dll+0x2732da]  AddNode::Value+0xda  (addnode.cpp:228)
V  [jvm.dll+0xe4f836]  PhaseIterGVN::transform_old+0x2a6  (phaseX.cpp:2151)
V  [jvm.dll+0xe4b13d]  PhaseIterGVN::optimize+0x2ad  (phaseX.cpp:1055)
V  [jvm.dll+0x5c2b2f]  Compile::Optimize+0xbaf  (compile.cpp:2511)
V  [jvm.dll+0x5bf819]  Compile::Compile+0x10f9  (compile.cpp:861)
V  [jvm.dll+0x4c3db9]  C2Compiler::compile_method+0x179  (c2compiler.cpp:150)
V  [jvm.dll+0x5ddad3]  CompileBroker::invoke_compiler_on_method+0x843  (compileBroker.cpp:2355)
V  [jvm.dll+0x5daebc]  CompileBroker::compiler_thread_loop+0x27c  (compileBroker.cpp:1990)
V  [jvm.dll+0x927171]  JavaThread::thread_main_inner+0x251  (javaThread.cpp:772)
V  [jvm.dll+0x105934e]  Thread::call_run+0x1be  (thread.cpp:248)
V  [jvm.dll+0xe001e4]  thread_native_entry+0xc4  (os_windows.cpp:555)
C  [ucrtbase.dll+0x14ea0]  (no source info available)
C  [KERNEL32.DLL+0x2dbe7]  (no source info available)
C  [ntdll.dll+0x85a6c]  (no source info available)
Comments
[~chagedorn] reduced it to this: java -XX:CompileCommand=quiet -XX:CompileCommand=compileonly,Reduced::test -XX:-TieredCompilation -Xbatch -XX:+StressIGVN -XX:RepeatCompilation=100 Reduced.java
10-11-2025
Okay, I confirmed that this is a duplicate of JDK-8371065. Closing. [~epeter] you might want to add the test to your PR, if that makes sense.
07-11-2025
[~epeter] Could you please have a look? Thanks. ILW = Assert during compilation due to unexpected types (regression in JDK 26), intermittent but reproducible, disable superword or compilation of affected method = HLM = P3
07-11-2025
Looks like a JDK 26 regression, narrowing it down.. Regression from JDK-8369448 in JDK 26. Maybe a dup of JDK-8371065?
07-11-2025