> An update: We were able to get around these issues by migrating our Linux builds to the bundled C++ library.
Ugh. Unfortunately, we had to go back to the system C++ library. It turns out that disabling C++ modules (use_clang_modules=false) was another way to resolve the original compilation errors. The only other divergence from the bullseye sysroot in 14.1 is the reliance on <source_location>, which was easy to patch since the sysroot has that header in the experimental subdirectory. On Tuesday, October 21, 2025 at 10:38:12 AM UTC-4 ClearScript Developers wrote: Thanks, Jakob. A clarification: The system C++ library on Windows still works. We were hoping to migrate our Windows build for consistency and future proofing but couldn't make it happen. That is, we could build the V8 monolith but not our embedder, seemingly due to some conflict between V8's libc++ and the Windows SDK somewhere deep in the header files. On Tuesday, October 21, 2025 at 10:04:02 AM UTC-4 Jakob Kummerow wrote: On Tue, Oct 21, 2025 at 3:40 PM ClearScript Developers <[email protected]> wrote: An update: We were able to get around these issues by migrating our Linux builds to the bundled C++ library. Support for system C++ libraries seems to be broken in 14.1, at least for Linux x64 and arm64. MacOS isn't affected but was easy to migrate, but we haven't been able to migrate our Windows build. Question for the V8 team: Is the removal of use_custom_libcxx imminent? We inherit that flag from Chromium's build configuration, so this would be a question for [email protected]. I only just found out that it is indeed marked deprecated since https://chromium-review.googlesource.com/c/chromium/src/+/5963336. M138 has passed, I don't know what the current plan is. The tracking bug <https://issues.chromium.org/issues/372852985> doesn't look like lots of activity recently. Personally I'd be fine with accepting (reasonably non-intrusive) community-supported patches that keep the system-libc++ build alive for the time being. On Tuesday, October 14, 2025 at 1:42:29 PM UTC-4 ClearScript Developers wrote: Greetings! While building the 14.1 branch tip on Linux, we're seeing compilation errors. Our configuration: fatal_linker_warnings = false is_cfi = false is_component_build = false is_debug = false target_cpu = "x64" use_custom_libcxx = false use_thin_lto = false v8_enable_fuzztest = false v8_enable_pointer_compression = false v8_enable_31bit_smis_on_64bit_arch = false v8_enable_temporal_support = false v8_monolithic = true v8_use_external_startup_data = false v8_target_cpu = "x64" The errors: FAILED: obj/build/modules/linux-x64/std_core/module.pcm ../../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/build/modules/linux-x64/std_core/module.pcm.d -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_GNU_SOURCE -DCR_CLANG_REVISION=\"llvmorg-21-init-16348-gbd809ffb-17\" -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -D_GLIBCXX_ASSERTIONS=1 -DCR_SYSROOT_KEY=20250129T203412Z-1 -DUSE_UDEV -DUSE_AURA=1 -DUSE_GLIB=1 -DUSE_OZONE=1 -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -D_LIBCPP_BUILDING_LIBRARY -I../../.. -Igen -fno-implicit-module-maps -fno-delete-null-pointer-checks -fno-strict-overflow -fno-ident -fno-math-errno -fno-strict-aliasing -fstack-protector -funwind-tables -fPIC -pthread -fcolor-diagnostics -fmerge-all-constants -fno-sized-deallocation -fcrash-diagnostics-dir=../../../tools/clang/crashreports -mllvm -instcombine-lower-dbg-declare=0 -mllvm -split-threshold-for-reg-with-hint=0 -ffp-contract=off -Wa,--crel,--allow-experimental-crel --target=x86_64-unknown-linux-gnu -msse3 -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -ffile-compilation-dir=. -no-canonical-prefixes -Xclang -fmodule-file-home-is-cwd -ftrivial-auto-var-init=pattern -O2 -fdata-sections -ffunction-sections -fno-unique-section-names -fno-omit-frame-pointer -g0 -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang check-stack-allocated -Xclang -plugin-arg-find-bad-constructs -Xclang check-ipc -Xclang -add-plugin -Xclang raw-ptr-plugin -Xclang -plugin-arg-raw-ptr-plugin -Xclang check-raw-ptr-to-stack-allocated -Xclang -plugin-arg-raw-ptr-plugin -Xclang disable-check-raw-ptr-to-stack-allocated-error -Xclang -plugin-arg-raw-ptr-plugin -Xclang raw-ptr-exclude-path=../../../third_party/dawn/ -Xclang -plugin-arg-raw-ptr-plugin -Xclang raw-ptr-exclude-path=../../../build/config/clang/chrome/test/fuzzing/webidl_fuzzing/ -fstrict-aliasing -Wundef -fPIC -Wall -Wno-unused-variable -Wno-c++11-narrowing -Wno-unused-but-set-variable -Wno-missing-field-initializers -Wno-unused-parameter -Wno-psabi -Wloop-analysis -Wno-unneeded-internal-declaration -Wno-cast-function-type -Wno-thread-safety-reference-return -Wno-nontrivial-memcall -Werror -Wno-exit-time-destructors -std=c++20 -Wno-trigraphs -gsimple-template-names -fno-exceptions -fno-rtti --sysroot=../../../build/linux/debian_bullseye_amd64-sysroot -fvisibility-inlines-hidden -fbuiltin-module-map -fmodule-map-file=gen/third_party/libc++/src/include/module.modulemap -fmodule-map-file=../../../build/modules/linux-x64/module.modulemap -std=c++20 -Wno-invalid-offsetof -Wenum-compare-conditional -Wno-nullability-completeness -fmodule-map-file=gen/third_party/libc++/src/include/module.modulemap -fbuiltin-module-map -fmodule-map-file=../../../build/modules/linux-x64/module.modulemap -fmodule-file=obj/build/modules/linux-x64/_Builtin_stdarg/module.pcm -fmodule-file=obj/build/modules/linux-x64/_Builtin_stddef/module.pcm -fmodule-file=obj/build/modules/linux-x64/_Builtin_stdint/module.pcm -fmodule-file=obj/build/modules/linux-x64/sys_stage1/module.pcm -fmodule-name=std_core -c -x c++ -Xclang -emit-module gen/third_party/libc++/src/include/module.modulemap -o obj/build/modules/linux-x64/std_core/module.pcm While building module 'std_core': In file included from <module-includes>:1: gen/third_party/libc++/src/include/__cstddef/byte.h:12:10: fatal error: '__config' file not found 12 | #include <__config> | ^~~~~~~~~~ 1 error generated. [1116/3269] CXX_MODULE obj/build/modules/linux-x64/std_ctype_h/module.pcm FAILED: obj/build/modules/linux-x64/std_ctype_h/module.pcm ../../../third_party/llvm-build/Release+Asserts/bin/clang++ -MMD -MF obj/build/modules/linux-x64/std_ctype_h/module.pcm.d -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_GNU_SOURCE -DCR_CLANG_REVISION=\"llvmorg-21-init-16348-gbd809ffb-17\" -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -D_GLIBCXX_ASSERTIONS=1 -DCR_SYSROOT_KEY=20250129T203412Z-1 -DUSE_UDEV -DUSE_AURA=1 -DUSE_GLIB=1 -DUSE_OZONE=1 -DNDEBUG -DNVALGRIND -DDYNAMIC_ANNOTATIONS_ENABLED=0 -D_LIBCPP_BUILDING_LIBRARY -I../../.. -Igen -fno-implicit-module-maps -fno-delete-null-pointer-checks -fno-strict-overflow -fno-ident -fno-math-errno -fno-strict-aliasing -fstack-protector -funwind-tables -fPIC -pthread -fcolor-diagnostics -fmerge-all-constants -fno-sized-deallocation -fcrash-diagnostics-dir=../../../tools/clang/crashreports -mllvm -instcombine-lower-dbg-declare=0 -mllvm -split-threshold-for-reg-with-hint=0 -ffp-contract=off -Wa,--crel,--allow-experimental-crel --target=x86_64-unknown-linux-gnu -msse3 -Wno-builtin-macro-redefined -D__DATE__= -D__TIME__= -D__TIMESTAMP__= -ffile-compilation-dir=. -no-canonical-prefixes -Xclang -fmodule-file-home-is-cwd -ftrivial-auto-var-init=pattern -O2 -fdata-sections -ffunction-sections -fno-unique-section-names -fno-omit-frame-pointer -g0 -fvisibility=hidden -Wheader-hygiene -Wstring-conversion -Wtautological-overlap-compare -Xclang -add-plugin -Xclang find-bad-constructs -Xclang -plugin-arg-find-bad-constructs -Xclang check-stack-allocated -Xclang -plugin-arg-find-bad-constructs -Xclang check-ipc -Xclang -add-plugin -Xclang raw-ptr-plugin -Xclang -plugin-arg-raw-ptr-plugin -Xclang check-raw-ptr-to-stack-allocated -Xclang -plugin-arg-raw-ptr-plugin -Xclang disable-check-raw-ptr-to-stack-allocated-error -Xclang -plugin-arg-raw-ptr-plugin -Xclang raw-ptr-exclude-path=../../../third_party/dawn/ -Xclang -plugin-arg-raw-ptr-plugin -Xclang raw-ptr-exclude-path=../../../build/config/clang/chrome/test/fuzzing/webidl_fuzzing/ -fstrict-aliasing -Wundef -fPIC -Wall -Wno-unused-variable -Wno-c++11-narrowing -Wno-unused-but-set-variable -Wno-missing-field-initializers -Wno-unused-parameter -Wno-psabi -Wloop-analysis -Wno-unneeded-internal-declaration -Wno-cast-function-type -Wno-thread-safety-reference-return -Wno-nontrivial-memcall -Werror -Wno-exit-time-destructors -std=c++20 -Wno-trigraphs -gsimple-template-names -fno-exceptions -fno-rtti --sysroot=../../../build/linux/debian_bullseye_amd64-sysroot -fvisibility-inlines-hidden -fbuiltin-module-map -fmodule-map-file=gen/third_party/libc++/src/include/module.modulemap -fmodule-map-file=../../../build/modules/linux-x64/module.modulemap -std=c++20 -Wno-invalid-offsetof -Wenum-compare-conditional -Wno-nullability-completeness -fmodule-map-file=gen/third_party/libc++/src/include/module.modulemap -fmodule-map-file=../../../build/modules/linux-x64/module.modulemap -fbuiltin-module-map -fmodule-file=obj/build/modules/linux-x64/_Builtin_stdarg/module.pcm -fmodule-file=obj/build/modules/linux-x64/_Builtin_stddef/module.pcm -fmodule-file=obj/build/modules/linux-x64/sys_stage1/module.pcm -fmodule-name=std_ctype_h -c -x c++ -Xclang -emit-module gen/third_party/libc++/src/include/module.modulemap -o obj/build/modules/linux-x64/std_ctype_h/module.pcm While building module 'std_ctype_h': In file included from <module-includes>:1: gen/third_party/libc++/src/include/ctype.h:35:12: error: '__config' file not found with <angled> include; use "quotes" instead 35 | # include <__config> | ^ While building module 'std_ctype_h': In file included from <module-includes>:1: In file included from gen/third_party/libc++/src/include/ctype.h:35: gen/third_party/libc++/src/include/__config:13:10: error: '__config_site' file not found with <angled> include; use "quotes" instead 13 | #include <__config_site> | ^ gen/third_party/libc++/src/include/__config:14:10: error: '__configuration/abi.h' file not found with <angled> include; use "quotes" instead 14 | #include <__configuration/abi.h> | ^ While building module 'std_ctype_h': In file included from <module-includes>:1: In file included from gen/third_party/libc++/src/include/ctype.h:35: In file included from gen/third_party/libc++/src/include/__config:14: gen/third_party/libc++/src/include/__configuration/abi.h:13:10: fatal error: '__config_site' file not found 13 | #include <__config_site> | ^~~~~~~~~~~~~~~ 4 errors generated. Full log attached. Can someone suggest a solution? -- -- -- v8-dev mailing list [email protected] http://groups.google.com/group/v8-dev --- You received this message because you are subscribed to the Google Groups "v8-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/v8-dev/954ec58e-d279-446c-acfe-ffce775812c0n%40googlegroups.com.
