1983897 - Perma [tier 2] /builds/worker/workspace/obj-build/dist/include/mozilla/MaybeStorageBase.h:66:25: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]

Status: RESOLVED FIXED

(Core :: MFBT, defect, P5)

Description

[Treeherder Bug Filer]

Filed by: chorotan [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=523015077&repo=mozilla-central&task=HbhWPzp7RbSNnTxQKJPuvg.2
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/HbhWPzp7RbSNnTxQKJPuvg/runs/2/artifacts/public/logs/live_backing.log

---

[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -      inlined from 'static void nsTArrayElementTraits<E>::Construct(E*) [with E = mozilla::Keyframe]' at /builds/worker/workspace/obj-build/dist/include/nsTArray.h:618:5,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -      inlined from 'nsTArray_Impl<E, Alloc>::value_type* nsTArray_Impl<E, Alloc>::AppendElementsInternal(nsTArray_Impl<E, Alloc>::size_type) [with ActualAlloc = nsTArrayInfallibleAllocator; E = mozilla::Keyframe; Alloc = nsTArrayInfallibleAllocator]' at /builds/worker/workspace/obj-build/dist/include/nsTArray.h:1764:29,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -      inlined from 'mozilla::NotNull<typename nsTArray_Impl<E, nsTArrayInfallibleAllocator>::value_type*> nsTArray<E>::AppendElement() [with E = mozilla::Keyframe]' at /builds/worker/workspace/obj-build/dist/include/nsTArray.h:2802:41,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -      inlined from 'nsTArray<mozilla::Keyframe> mozilla::dom::BuildGroupKeyframes(mozilla::dom::Document*, const CSSToCSSMatrix4x4Flagged&, const nsSize&, const mozilla::StyleOwnedSlice<mozilla::StyleGenericFilter<mozilla::StyleAngle, float, float, mozilla::StyleCSSPixelLength, mozilla::StyleGenericSimpleShadow<mozilla::StyleGenericColor<mozilla::StylePercentage>, mozilla::StyleCSSPixelLength, mozilla::StyleCSSPixelLength>, mozilla::StyleComputedUrl> >&)' at /builds/worker/checkouts/gecko/dom/view-transitions/ViewTransition.cpp:713,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -      inlined from 'void mozilla::dom::ViewTransition::SetupTransitionPseudoElements()' at /builds/worker/checkouts/gecko/dom/view-transitions/ViewTransition.cpp:939:
[task 2025-08-19T17:18:06.893+00:00] 17:18:06    ERROR -  /builds/worker/workspace/obj-build/dist/include/mozilla/MaybeStorageBase.h:66:25: error: writing 1 byte into a region of size 0 [-Werror=stringop-overflow=]
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -     66 |     constexpr Union() : empty() {}
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -        |                         ^~~~~~~
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -  In file included from /builds/worker/workspace/obj-build/ipc/ipdl/_ipdlheaders/mozilla/layers/WebRenderMessages.h:13,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -                   from /builds/worker/workspace/obj-build/dist/include/mozilla/layers/IpcResourceUpdateQueue.h:10,
[task 2025-08-19T17:18:06.893+00:00] 17:18:06     INFO -                   from /builds/worker/checkouts/gecko/dom/view-transitions/ViewTransition.h:9,
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -                   from /builds/worker/checkouts/gecko/dom/view-transitions/ViewTransition.cpp:5,
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -                   from Unified_cpp_dom_view-transitions0.cpp:2:
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -  /builds/worker/workspace/obj-build/dist/include/nsTArray.h: In member function 'void mozilla::dom::ViewTransition::SetupTransitionPseudoElements()':
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -  /builds/worker/workspace/obj-build/dist/include/nsTArray.h:276:29: note: at offset 8 into destination object 'sEmptyTArrayHeader' of size 8
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -    276 | extern const nsTArrayHeader sEmptyTArrayHeader;
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -        |                             ^~~~~~~~~~~~~~~~~~
[task 2025-08-19T17:18:06.894+00:00] 17:18:06     INFO -  cc1plus: all warnings being treated as errors
[task 2025-08-19T17:18:06.895+00:00] 17:18:06    ERROR -  gmake[4]: *** [/builds/worker/checkouts/gecko/config/rules.mk:670: Unified_cpp_dom_view-transitions0.o] Error 1
[task 2025-08-19T17:18:06.895+00:00] 17:18:06     INFO -  gmake[4]: Leaving directory '/builds/worker/workspace/obj-build/dom/view-transitions'
[task 2025-08-19T17:18:06.895+00:00] 17:18:06     INFO -  gmake[4]: Target 'target-objects' not remade because of errors.
[task 2025-08-19T17:18:06.895+00:00] 17:18:06    ERROR -  gmake[3]: *** [/builds/worker/checkouts/gecko/config/recurse.mk:72: dom/view-transitions/target-objects] Error 2
[task 2025-08-19T17:18:06.895+00:00] 17:18:06     INFO -  gmake[4]: Entering directory '/builds/worker/workspace/obj-build/intl/lwbrk'
[task 2025-08-19T17:18:06.895+00:00] 17:18:06     INFO -  intl/lwbrk/Unified_cpp_intl_lwbrk0.o
[task 2025-08-19T17:18:06.895+00:00] 17:18:06     INFO -  gmake[4]: Leaving directory '/builds/worker/workspace/obj-build/intl/lwbrk'
[task 2025-08-19T17:18:06.983+00:00] 17:18:06     INFO -  gmake[4]: Entering directory '/builds/worker/workspace/obj-build/gfx/angle/targets/translator'
[task 2025-08-19T17:18:06.985+00:00] 17:18:06     INFO -  /builds/worker/fetches/sccache/sccache /builds/worker/fetches/gcc/bin/g++ --sysroot /builds/worker/fetches/sysroot-x86_64-linux-gnu -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/c++/8 -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/x86_64-linux-gnu/c++/8 -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/x86_64-linux-gnu -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include -o glslang_tab_autogen.o -c  -I/builds/worker/workspace/obj-build/dist/stl_wrappers -I/builds/worker/workspace/obj-build/dist/system_wrappers -include /builds/worker/checkouts/gecko/config/gcc_hidden.h -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fstack-protector-strong -DNDEBUG=1 -DTRIMMED=1 -DANGLE_PLATFORM_EXPORT= -D__NDK_FPABI__= -DANGLE_SKIP_DXGI_1_2_CHECK -DANGLE_ENABLE_KEYEDMUTEX -DANGLE_TRANSLATOR_ESSL_ONLY -DANGLE_DISABLE_POOL_ALLOC -DANGLE_ENABLE_APPLE_WORKAROUNDS -DANGLE_ENABLE_ESSL -DANGLE_ENABLE_GLSL -DANGLE_ENABLE_HLSL -DANGLE_ENABLE_SHARE_CONTEXT_LOCK=1 -DANGLE_VMA_VERSION=2003000 '-DCR_CLANG_REVISION="llvmorg-16-init-6578-g0d30e92f-2"' -DDYNAMIC_ANNOTATIONS_ENABLED=0 -DNOMINMAX -DUNICODE -DWINVER=0x0A00 -D_ATL_NO_OPENGL -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_RAND_S -D_CRT_SECURE_NO_DEPRECATE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SECURE_ATL -D_UNICODE -D_WINSOCK_DEPRECATED_NO_WARNINGS -I/builds/worker/checkouts/gecko/gfx/angle/targets/translator -I/builds/worker/workspace/obj-build/gfx/angle/targets/translator -I/builds/worker/checkouts/gecko/gfx/angle/checkout/include -I/builds/worker/checkouts/gecko/gfx/angle/checkout/src -I/builds/worker/checkouts/gecko/gfx/angle/checkout/src/common/third_party/base -I/builds/worker/workspace/obj-build/dist/include -I/builds/worker/workspace/obj-build/dist/include/nspr -I/builds/worker/workspace/obj-build/dist/include/nss -DMOZILLA_CLIENT -include /builds/worker/workspace/obj-build/mozilla-config.h -D_GLIBCXX_USE_CXX11_ABI=0 -fno-rtti -pthread -fno-sized-deallocation -fno-aligned-new -ffunction-sections -fdata-sections -fno-math-errno -fno-exceptions -pipe -fPIC -gdwarf-4 -O2 -fno-omit-frame-pointer -funwind-tables -Wall -Wempty-body -Wignored-qualifiers -Wpointer-arith -Wsign-compare -Wtype-limits -Wunreachable-code -Wno-invalid-offsetof -Wcomma-subscript -Wvolatile -Wno-deprecated-enum-enum-conversion -Wduplicated-cond -Wimplicit-fallthrough -Wlogical-op -Wno-error=maybe-uninitialized -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-multistatement-macros -Wno-error=class-memaccess -Wformat -Wformat-overflow=2 -Wno-psabi -Wno-error=builtin-macro-redefined -I/builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include -msse2 -fno-strict-aliasing -ffp-contract=off  -MD -MP -MF .deps/glslang_tab_autogen.o.pp   /builds/worker/checkouts/gecko/gfx/angle/checkout/src/compiler/translator/glslang_tab_autogen.cpp
[task 2025-08-19T17:18:06.985+00:00] 17:18:06     INFO -  gmake[4]: Leaving directory '/builds/worker/workspace/obj-build/gfx/angle/targets/translator'
[task 2025-08-19T17:18:06.985+00:00] 17:18:06     INFO -  gmake[4]: Entering directory '/builds/worker/workspace/obj-build/gfx/angle/targets/translator'
[task 2025-08-19T17:18:06.985+00:00] 17:18:06     INFO -  gmake[4]: Leaving directory '/builds/worker/workspace/obj-build/gfx/angle/targets/translator'
[task 2025-08-19T17:18:06.986+00:00] 17:18:06     INFO -  gmake[4]: Entering directory '/builds/worker/workspace/obj-build/intl/components'
[task 2025-08-19T17:18:06.988+00:00] 17:18:06     INFO -  /builds/worker/fetches/sccache/sccache /builds/worker/fetches/gcc/bin/g++ --sysroot /builds/worker/fetches/sysroot-x86_64-linux-gnu -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/c++/8 -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/x86_64-linux-gnu/c++/8 -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include/x86_64-linux-gnu -isystem /builds/worker/fetches/sysroot-x86_64-linux-gnu/usr/include -o Unified_cpp_intl_components0.o -c  -I/builds/worker/workspace/obj-build/dist/stl_wrappers -I/builds/worker/workspace/obj-build/dist/system_wrappers -include /builds/worker/checkouts/gecko/config/gcc_hidden.h -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fstack-protector-strong -DNDEBUG=1 -DTRIMMED=1 -DMOZ_HAS_MOZGLUE -I/builds/worker/checkouts/gecko/intl/components -I/builds/worker/workspace/obj-build/intl/components -I/builds/worker/checkouts/gecko/intl/icu_capi/bindings/cpp -I/builds/worker/workspace/obj-build/dist/include -I/builds/worker/workspace/obj-build/dist/include/nspr -I/builds/worker/workspace/obj-build/dist/include/nss -DMOZILLA_CLIENT -include /builds/worker/workspace/obj-build/mozilla-config.h -D_GLIBCXX_USE_CXX11_ABI=0 -fno-rtti -pthread -fno-sized-deallocation -fno-aligned-new -ffunction-sections -fdata-sections -fno-math-errno -fno-exceptions -pipe -fPIC -gdwarf-4 -O2 -fno-omit-frame-pointer -funwind-tables -Werror -Wall -Wempty-body -Wignored-qualifiers -Wpointer-arith -Wsign-compare -Wtype-limits -Wunreachable-code -Wno-invalid-offsetof -Wcomma-subscript -Wvolatile -Wno-deprecated-enum-enum-conversion -Wduplicated-cond -Wimplicit-fallthrough -Wlogical-op -Wno-error=maybe-uninitialized -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-multistatement-macros -Wno-error=class-memaccess -Wformat -Wformat-overflow=2 -Wno-psabi -Wno-error=builtin-macro-redefined -fno-strict-aliasing -ffp-contract=off  -MD -MP -MF .deps/Unified_cpp_intl_components0.o.pp   Unified_cpp_intl_components0.cpp
[task 2025-08-19T17:18:06.988+00:00] 17:18:06     INFO -  In file included from Unified_cpp_intl_components0.cpp:29:
[task 2025-08-19T17:18:06.988+00:00] 17:18:06     INFO -  /builds/worker/checkouts/gecko/intl/components/src/Collator.cpp: In member function 'void mozilla::intl::Collator::SetStrength(mozilla::intl::Collator::Strength)':
[task 2025-08-19T17:18:06.988+00:00] 17:18:06  WARNING -  /builds/worker/checkouts/gecko/intl/components/src/Collator.cpp:106:19: warning: 'strength' may be used uninitialized in this function [-Wmaybe-uninitialized]
[task 2025-08-19T17:18:06.989+00:00] 17:18:06     INFO -    106 |   ucol_setStrength(mCollator.GetMut(), strength);

Comment 1

[Cristina Horotan [:chorotan]]

Nicolas,
Could your push from https://bugzilla.mozilla.org/show_bug.cgi?id=1964101#c7 cause this failure?

Comment 2

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 1964101

Comment 3

[Nicolas Silva [:nical]]

Probably not. The error is in nearby but unrelated code. Looks like gcc is getting confused about nsTarray's AppendElement() without input element.
I have a workaround that seems to work.

Comment 4

[Nicolas Silva [:nical]]

Attachment: Bug 1983897 - Work around a gcc warning. r=emilio

Looks like gcc is getting confused about something in this AppendElement overload, maybe in conjunction with the enum in a Maybe<float> contained in the KeyFrame.
I don't know why this just started failing.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/3d2cca16702a
https://hg.mozilla.org/integration/autoland/rev/907c7b08aa82
Work around a gcc warning. r=emilio

Comment 6

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/907c7b08aa82

Comment 7

[Intermittent Failures Robot]

6 failures were associated with this bug in the last 7 days.

Repository breakdown:

• mozilla-central: 6

Table

	no_variant
linux64-x86/opt	6

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1983897&startday=2025-08-18&endday=2025-08-24&tree=all