deps: Bump V8 13.8.258.26 -> 14.6.202.10, simdutf 7.3.4 -> 8.1.0, fp16 by jwendell · Pull Request #43928 · envoyproxy/envoy

jwendell · 2026-03-12T12:21:40Z

Bump V8 to 14.6.202.10 which converts JSDispatchTable from per-IsolateGroup to per-Isolate (commit 4d1e2794e), eliminating the race condition in concurrent Isolate creation that caused crashes in Wasm VM cloning.

Dependency updates required by V8 14.6:

simdutf 7.3.4 -> 8.1.0 (V8 now uses atomic simdutf functions)
fp16 updated to revision 3d2de1816 (matches V8 14.6 bundled version)

Workarounds for LLVM 18 toolchain compatibility (all marked with TODO(jwendell) for removal once LLVM is bumped to 19+):

std::atomic_ref polyfill: LLVM 18's libc++ does not provide std::atomic_ref (C++20 P0019R8). V8 14.6 and simdutf use it pervasively. A polyfill header is injected into both V8 and simdutf via patches/patch_cmds using reinterpret_cast<std::atomic*>.
consteval -> constexpr: clang 18 has bugs with consteval in certain template instantiation contexts (e.g. regexp-bytecodes-inl.h). All consteval occurrences in V8 are downgraded to constexpr, which is strictly more permissive and functionally safe.
ShuffleArray<>: clang 18 does not support default template argument deduction on alias templates without explicit <>.

Other V8 14.6 patch updates:

Remove @libcxx//:libc++ from V8 deps (Envoy uses its own toolchain)
Remove -latomic linker flag
Add -Wno-invalid-offsetof, -Wno-dangling-pointer, -Wno-dangling-reference
Add macros.h to fp16.BUILD for new fp16 revision

repokitteh-read-only · 2026-03-12T12:21:48Z

As a reminder, PRs marked as draft will not be automatically assigned reviewers,
or be handled by maintainer-oncall triage.

Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #43928 was opened by jwendell.

see: more, trace.

phlax · 2026-03-12T12:42:19Z

dragonbox, highway and fast_float might also want to be updated - they were all picked/pinned to the version that v8 was using

jwendell · 2026-03-12T12:56:32Z

dragonbox, highway and fast_float might also want to be updated - they were all picked/pinned to the version that v8 was using

Dep	Status
V8	13.8.258.26 → 14.6.202.10 ✅
simdutf	7.3.4 → 8.1.0 ✅
fp16	Updated to match V8 14.6 ✅
fast_float	7.0.0 — already matches V8 14.6 ✅
dragonbox	6c7c925 — already matches V8 14.6 ✅
highway	1.2.0 — newer than V8 14.6's bundled version ✅
proxy_wasm_cpp_host	beb8a4e (Jan 2026) — uses V8 14.4, compatible ✅

Bump V8 to 14.6.202.10 which converts JSDispatchTable from per-IsolateGroup to per-Isolate (commit 4d1e2794e), eliminating the race condition in concurrent Isolate creation that caused crashes in Wasm VM cloning. Dependency updates required by V8 14.6: - simdutf 7.3.4 -> 8.1.0 (V8 now uses atomic simdutf functions) - fp16 updated to revision 3d2de1816 (matches V8 14.6 bundled version) Workarounds for LLVM 18 toolchain compatibility (all marked with TODO(jwendell) for removal once LLVM is bumped to 19+): - std::atomic_ref polyfill: LLVM 18's libc++ does not provide std::atomic_ref (C++20 P0019R8). V8 14.6 and simdutf use it pervasively. A polyfill header is injected into both V8 and simdutf via patches/patch_cmds using reinterpret_cast<std::atomic<T>*>. - consteval -> constexpr: clang 18 has bugs with consteval in certain template instantiation contexts (e.g. regexp-bytecodes-inl.h). All consteval occurrences in V8 are downgraded to constexpr, which is strictly more permissive and functionally safe. - ShuffleArray<>: clang 18 does not support default template argument deduction on alias templates without explicit <>. Other V8 14.6 patch updates: - Remove @libcxx//:libc++ from V8 deps (Envoy uses its own toolchain) - Remove -latomic linker flag - Add -Wno-invalid-offsetof, -Wno-dangling-pointer, -Wno-dangling-reference - Add macros.h to fp16.BUILD for new fp16 revision Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com> Signed-off-by: Jonh Wendell <jwendell@redhat.com>

repokitteh-read-only · 2026-03-12T16:39:47Z

CC @envoyproxy/dependency-shepherds: Your approval is needed for changes made to (bazel/.*repos.*\.bzl)|(bazel/dependency_imports\.bzl)|(api/bazel/.*\.bzl)|(.*/requirements\.txt)|(.*\.patch).
envoyproxy/dependency-shepherds assignee is @RyanTheOptimist

🐱

Caused by: #43928 was ready_for_review by jwendell.

see: more, trace.

phlax

lgtm, thanks @jwendell

phlax · 2026-03-12T18:08:43Z

+            "grep -rl 'std::atomic_ref' src/ include/ --include='*.h' --include='*.cc' | grep -v atomic_ref_polyfill | xargs -r sed -i '1s!^!#include \"src/base/atomic_ref_polyfill.h\"\\n!'",
+            # TODO(jwendell): Remove consteval->constexpr workaround once the LLVM toolchain is
+            # bumped. Clang 18 has bugs with consteval in template contexts (fixed in clang 19+).
+            "find ./src -type f \\( -name '*.h' -o -name '*.cc' \\) -exec sed -i 's/consteval/constexpr/g' {} \\;",


these will be pain to rework in bzlmod - no patch_cmds

envoyproxy#43928) Bump V8 to 14.6.202.10 which converts JSDispatchTable from per-IsolateGroup to per-Isolate (commit 4d1e2794e), eliminating the race condition in concurrent Isolate creation that caused crashes in Wasm VM cloning. Dependency updates required by V8 14.6: - simdutf 7.3.4 -> 8.1.0 (V8 now uses atomic simdutf functions) - fp16 updated to revision 3d2de1816 (matches V8 14.6 bundled version) Workarounds for LLVM 18 toolchain compatibility (all marked with TODO(jwendell) for removal once LLVM is bumped to 19+): - std::atomic_ref polyfill: LLVM 18's libc++ does not provide std::atomic_ref (C++20 P0019R8). V8 14.6 and simdutf use it pervasively. A polyfill header is injected into both V8 and simdutf via patches/patch_cmds using reinterpret_cast<std::atomic<T>*>. - consteval -> constexpr: clang 18 has bugs with consteval in certain template instantiation contexts (e.g. regexp-bytecodes-inl.h). All consteval occurrences in V8 are downgraded to constexpr, which is strictly more permissive and functionally safe. - ShuffleArray<>: clang 18 does not support default template argument deduction on alias templates without explicit <>. Other V8 14.6 patch updates: - Remove @libcxx//:libc++ from V8 deps (Envoy uses its own toolchain) - Remove -latomic linker flag - Add -Wno-invalid-offsetof, -Wno-dangling-pointer, -Wno-dangling-reference - Add macros.h to fp16.BUILD for new fp16 revision Signed-off-by: Jonh Wendell <jwendell@redhat.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Signed-off-by: bjmask <11672696+bjmask@users.noreply.github.com>

envoyproxy#43928) Bump V8 to 14.6.202.10 which converts JSDispatchTable from per-IsolateGroup to per-Isolate (commit 4d1e2794e), eliminating the race condition in concurrent Isolate creation that caused crashes in Wasm VM cloning. Dependency updates required by V8 14.6: - simdutf 7.3.4 -> 8.1.0 (V8 now uses atomic simdutf functions) - fp16 updated to revision 3d2de1816 (matches V8 14.6 bundled version) Workarounds for LLVM 18 toolchain compatibility (all marked with TODO(jwendell) for removal once LLVM is bumped to 19+): - std::atomic_ref polyfill: LLVM 18's libc++ does not provide std::atomic_ref (C++20 P0019R8). V8 14.6 and simdutf use it pervasively. A polyfill header is injected into both V8 and simdutf via patches/patch_cmds using reinterpret_cast<std::atomic<T>*>. - consteval -> constexpr: clang 18 has bugs with consteval in certain template instantiation contexts (e.g. regexp-bytecodes-inl.h). All consteval occurrences in V8 are downgraded to constexpr, which is strictly more permissive and functionally safe. - ShuffleArray<>: clang 18 does not support default template argument deduction on alias templates without explicit <>. Other V8 14.6 patch updates: - Remove @libcxx//:libc++ from V8 deps (Envoy uses its own toolchain) - Remove -latomic linker flag - Add -Wno-invalid-offsetof, -Wno-dangling-pointer, -Wno-dangling-reference - Add macros.h to fp16.BUILD for new fp16 revision Signed-off-by: Jonh Wendell <jwendell@redhat.com> Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

jwendell force-pushed the bump-v8 branch 3 times, most recently from 081c67e to 85c450c Compare March 12, 2026 15:08

jwendell force-pushed the bump-v8 branch from 85c450c to e643000 Compare March 12, 2026 15:37

jwendell marked this pull request as ready for review March 12, 2026 16:39

repokitteh-read-only bot added the deps Approval required for changes to Envoy's external dependencies label Mar 12, 2026

repokitteh-read-only bot assigned RyanTheOptimist Mar 12, 2026

phlax approved these changes Mar 12, 2026

View reviewed changes

repokitteh-read-only bot removed the deps Approval required for changes to Envoy's external dependencies label Mar 12, 2026

jwendell merged commit 3cb0d8f into envoyproxy:main Mar 12, 2026
29 of 30 checks passed

jwendell mentioned this pull request Mar 14, 2026

wasm: fix race condition in concurrent V8 Isolate creation during dyamic WASM loading #43746

Closed

adam-cattermole linked an issue Mar 31, 2026 that may be closed by this pull request

Envoy Data-plane pods crash on first auth/ratelimit policy deployment Kuadrant/wasm-shim#314

Closed

averevki mentioned this pull request Apr 17, 2026

test(x509): add Tier 1, Client-Cert header and multi CA trust tests Kuadrant/testsuite#936

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deps: Bump V8 13.8.258.26 -> 14.6.202.10, simdutf 7.3.4 -> 8.1.0, fp16#43928

deps: Bump V8 13.8.258.26 -> 14.6.202.10, simdutf 7.3.4 -> 8.1.0, fp16#43928
jwendell merged 1 commit intoenvoyproxy:mainfrom
jwendell:bump-v8

jwendell commented Mar 12, 2026

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