What causes "visit instance failed, lost type def of typeId: " in Tencent/matrix?

Re-capture the heap dump to replace a corrupted file.

Tencent/matrix · error · IllegalStateException

visit instance failed, lost type def of typeId:

Error message

visit instance failed, lost type def of typeId:

What it means

In the general instance-visiting path, HprofBufferShrinker again resolves each Bitmap class field type via Type.getType(field.typeId) to skip fields until it reaches mBuffer. A null Type means the dump has no definition for that typeId, so the parser cannot compute the field size (skipValue) and throws IllegalStateException to avoid misparsing the binary stream.

Solutions

Re-capture the heap dump to replace a corrupted file.
Align the Matrix version with the device/runtime that produced the hprof.
Pre-validate the hprof structure (e.g. parse the class dump section independently) before shrinking.
Handle IllegalStateException during parse and fall back to uploading the raw hprof.

Defensive patterns

Strategy: try-catch

Validate before calling

if (hprofFile.length() == 0) {
    throw new IOException("empty hprof: " + hprofFile);
}

Try / catch

try {
    shrinker.shrink(hprof, out);
} catch (IllegalStateException e) {
    Log.e(TAG, "instance visit failed, keep raw hprof", e);
}

Prevention

Avoid post-processing hprof files with third-party tools before Matrix parses them.
Re-capture corrupted dumps instead of retrying.
Match parser Type tables to the device ART version.

When it happens

Trigger: visitHeapDumpInstance encounters mBmpClassInstanceFields containing a Field whose typeId has no Type definition while scanning for the mBuffer field.

Common situations: Truncated or partially written hprof; dumps from a runtime version mismatched with the parser's Type table; hprof files manually converted by other tools.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

AI-assisted analysis of Tencent/matrix@3b8293bd65 (2026-09-08). Data as JSON: /api/errors/378a3b50ec5d8792. Report an issue: GitHub.

Appendix: source

Thrown at matrix/matrix-android/matrix-resource-canary/matrix-resource-canary-android/src/main/java/com/tencent/matrix/resource/hproflib/HprofBufferShrinker.java:364

        HprofBufferShrinkVisitor(HprofWriter hprofWriter) {
            super(hprofWriter);
        }

        @Override
        public HprofHeapDumpVisitor visitHeapDumpRecord(int tag, int timestamp, long length) {
            return new HprofHeapDumpVisitor(super.visitHeapDumpRecord(tag, timestamp, length)) {
                @Override
                public void visitHeapDumpInstance(ID id, int stackId, ID typeId, byte[] instanceData) {
                    try {
                        if (typeId.equals(mBmpClassId)) {
                            ID bufferId = null;
                            int bufferIdPos = 0;
                            final ByteArrayInputStream bais = new ByteArrayInputStream(instanceData);
                            for (Field field : mBmpClassInstanceFields) {
                                final ID fieldNameStringId = field.nameId;
                                final Type fieldType = Type.getType(field.typeId);
                                if (fieldType == null) {
                                    throw new IllegalStateException("visit instance failed, lost type def of typeId: " + field.typeId);
                                }
                                if (mMBufferFieldNameStringId.equals(fieldNameStringId)) {
                                    bufferId = (ID) IOUtil.readValue(bais, fieldType, mIdSize);
                                    break;
                                } else {
                                    bufferIdPos += IOUtil.skipValue(bais, fieldType, mIdSize);
                                }
                            }
                            if (bufferId != null) {
                                final ID deduplicatedId = mBmpBufferIdToDeduplicatedIdMap.get(bufferId);
                                if (deduplicatedId != null && !bufferId.equals(deduplicatedId) && !bufferId.equals(mNullBufferId)) {
                                    modifyIdInBuffer(instanceData, bufferIdPos, deduplicatedId);
                                }
                            }
                        }
                    } catch (Throwable thr) {
                        throw new RuntimeException(thr);
                    }

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