[kaahos]

Summary

• decodeAdrTarget() left-shifts the sign-extended ADRP immediate (imm << 12), which is undefined behavior when imm is negative (ADRP addresses pages in either direction relative to PC)
• UBSan traps this on every forked test JVM during VM::initProfilerBridge -> JvmtiEnv::GenerateEvents -> analyzeStubUnwind, aborting the process almost immediately (checks are compiled non-recoverable via -fno-sanitize-recover=all)
• Fix: cast to uint64_t before shifting, matching the existing attributionPC pattern in this codebase for the same UB class -- two's-complement wraparound produces an identical bit pattern, just well-defined
• Reference: https://en.cppreference.com/w/cpp/language/operator_arithmetic.html (bitwise shift operators -- left shift of a negative value is undefined behavior before C++20)

Test plan

• gtestAsan / testAsan on aarch64 no longer aborts with the UBSan left-shift error

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-09T10:12:56.423302Z	803e1ed	Draft marked ready

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 803e1edd5a

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[datadog-prod-us1-4]

More details

Casting to uint64_t before shifting preserves ADRP page offsets, including negative immediates, while removing the signed-shift undefined behavior.

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[dd-octo-sts]

CI Test Results

Run: #37919030165 | Commit: 39510de | Duration: 22m 30s (longest job)

✅ All 76 test jobs passed

Status Overview

JDK	glibc-aarch64/asan	glibc-aarch64/debug	glibc-aarch64/tsan	glibc-amd64/asan	glibc-amd64/debug	glibc-amd64/tsan	musl-aarch64/debug	musl-amd64/debug
8	-	-	-	✅	✅	✅	-	-
8-ibm	-	-	-	✅	✅	✅	-	-
8-j9	✅	✅	✅	✅	✅	✅	-	-
8-librca	-	-	-	-	-	-	✅	✅
8-orcl	-	-	-	✅	✅	✅	-	-
11	-	-	-	✅	✅	✅	-	-
11-j9	✅	✅	✅	✅	✅	✅	-	-
11-librca	-	-	-	-	-	-	✅	✅
17	✅	✅	✅	✅	✅	✅	-	-
17-graal	✅	✅	✅	✅	✅	✅	-	-
17-j9	✅	✅	✅	✅	✅	✅	-	-
17-librca	-	-	-	-	-	-	✅	✅
21	✅	✅	✅	✅	✅	✅	-	-
21-graal	✅	✅	✅	✅	✅	✅	-	-
21-librca	-	-	-	-	-	-	✅	✅
25	✅	✅	✅	✅	✅	✅	-	-
25-graal	✅	✅	✅	✅	✅	✅	-	-
25-librca	-	-	-	-	-	-	✅	✅

Legend: ✅ passed | ❌ failed | ⚪ skipped | 🚫 cancelled

Summary: Total: 76 | Passed: 76 | Failed: 0

---

Updated: 2026-10-09 11:07:08 UTC

[dd-octo-sts]

✅ All 40 integration tests passed

📊 Dashboard · 👷 Pipeline · 📦 da2494ac

[dd-octo-sts]

Reliability & Chaos Results

✅ All reliability & chaos checks passed Pipeline: https://gitlab.ddbuild.io/DataDog/java-profiler/-/pipelines/143670108