ext/intl: fix clang build.

[devnexen]

actually, with recent icu releases, this problem arises

checking whether clang++ supports C++17 features with -std=c++17... no
checking whether clang++ supports C++17 features with +std=c++17... no
checking whether clang++ supports C++17 features with -h std=c++17... no
checking whether clang++ supports C++17 features with -std=c++1z... no
checking whether clang++ supports C++17 features with +std=c++1z... no
checking whether clang++ supports C++17 features with -h std=c++1z... no
configure: error: *** A compiler with support for C++17 language features is required.

thus, proposing to falls into LLVM libc++ instead.

[devnexen]

note it happens only when ubsan is enabled.

[devnexen]

so intl itself might be compiled with rtti however we compile c++ w/o exceptions nor rtti (lean binaries ?) so had to disable vptr sanitizer check.

[iluuu1994]

Sadly, I'm not very qualified to review this. 🙁 Maybe @petk can help?

[devnexen]

Sadly, I'm not very qualified to review this. 🙁 Maybe @petk can help?

fair enough :) I suspect this might be one of the reasons @YuanchengJiang never build intl with clang (this PR fixes two distinct issues).

[petk]

Hello, I can't seem to reproduce exactly this kind issue (but a whole lots of other ones unrelated to this issue :D). I've checked master branch, clang 18 (with llvm installed and without), clang 19, ICU library 74, with this:

CC=clang CXX=clang++ ./configure --enable-intl --enable-undefined-sanitizer

I have no idea. Does perhaps installing llvm library for that clang compiler help?

[devnexen]

Hello, I can't seem to reproduce exactly this kind issue (but a whole lots of other ones unrelated to this issue :D). I've checked master branch, clang 18 (with llvm installed and without), clang 19, ICU library 74, with this:

CC=clang CXX=clang++ ./configure --enable-intl --enable-undefined-sanitizer

I have no idea. Does perhaps installing llvm library for that clang compiler help?

@petk long time no see :) did you try to build ? indeed with my other machine configure part pass but I stumble across linkage issue and yes I have llvm-dev/llvm installed. I may retry in the other machine which has clang 20 for the other problem. Cheers.

[devnexen]

Here a taste of what I get

/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5d6e): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5d8b): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5e57): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5e74): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5f87): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x5fa4): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x60e9): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:226:(.text+0x6106): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:228:(.text+0x616e): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:228:(.text+0x618b): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: ext/intl/breakiterator/codepointiterator_internal.o: in function `PHP::CodePointBreakIterator::refreshInputText(UText*, UErrorCode&)':
/home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:284:(.text+0x6687): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:284:(.text+0x66a1): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:285:(.text+0x66f6): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:285:(.text+0x6710): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:285:(.text+0x6774): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:285:(.text+0x678e): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:290:(.text+0x6857): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:290:(.text+0x6871): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:291:(.text+0x68c3): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.cpp:291:(.text+0x68dd): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: ext/intl/breakiterator/codepointiterator_internal.o: in function `PHP::CodePointBreakIterator::clearCurrentCharIter()':
/home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:96:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x76): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:96:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x90): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:96:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x11f): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:96:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x139): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:97:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x183): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:97:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x19d): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:98:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x1e6): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /home/dcarlier/Contribs/php-src/ext/intl/breakiterator/codepointiterator_internal.h:98:(.text._ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv[_ZN3PHP22CodePointBreakIterator20clearCurrentCharIterEv]+0x200): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: ext/intl/breakiterator/codepointiterator_internal.o: in function `std::type_info::operator!=(std::type_info const&) const':
/usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14/typeinfo:114:(.text._ZNKSt9type_infoneERKS_[_ZNKSt9type_infoneERKS_]+0x7a): undefined reference to `__ubsan_vptr_type_cache'
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14/typeinfo:114:(.text._ZNKSt9type_infoneERKS_[_ZNKSt9type_infoneERKS_]+0x94): undefined reference to `__ubsan_handle_dynamic_type_cache_miss_abort'
/usr/bin/ld: ext/intl/breakiterator/codepointiterator_internal.o: in function `std::type_info::operator==(std::type_info const&) const':

this change fixes it. since we compile C++ with -fno-rtti -fno-exceptions and the sanitizer relies on type_info so ..

[iluuu1994]

@devnexen I've experienced this issue in the past, and I believe linking with Clang++ fixes the issue, but I didn't know how to best achieve this in the build system.

[petk]

did you try to build ?

Yes, I see. Link step fails the same as yours, yes. And adding the ,vptr fixes this.

[devnexen]

@devnexen I've experienced this issue in the past, and I believe linking with Clang++ fixes the issue, but I didn't know how to best achieve this in the build system.

I won t mind just pushing just the ubsan change, the other part might be a bit "heavy" as forcing to use llvm c++ runtime but I may retest this a bit later.