<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/119608>119608</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
Undefined symbols for "typeinfo for __int128" when using Clang and libc++ on macOS
</td>
</tr>
<tr>
<th>Labels</th>
<td>
clang,
libc++
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
ArseniyKholod
</td>
</tr>
</table>
<pre>
I have encountered a linker issue when compiling code with Clang and libc++ on macOS on macOS that involves `typeid(__int128)`. The compilation succeeds, but linking fails with the following error: `Undefined symbols for architecture arm64: "typeinfo for __int128" `. The same happens on x86_64.
It appears that `__int128` itself is supported as a type, but the runtime type information (`typeid`) for it is not being resolved by the linker.
Minimal working example (MWE):
test_clang.cpp:
```
#include <iostream>
#include <string>
#include <typeinfo>
int main()
{
__int128 t = 1234567890;
std::cout << typeid(__int128).name();
return 0;
}
```
Compilation command: `/opt/homebrew/opt/llvm/bin/clang++ test_clang.cpp -stdlib=libc++ -std=gnu++17 -frtti -v`
If the `typeid` line is commented out, the code compiles and links without issues.
Is there a workaround to use `typeid` with `__int128`?
Will support for typeinfo on `__int128` be implemented in future versions of Clang/libc++?
The full error message:
```bash-3.2$ /opt/homebrew/opt/llvm/bin/clang++ test_clang.cpp -stdlib=libc++ -std=gnu++17 -frtti -v
Homebrew clang version 19.1.4
Target: arm64-apple-darwin23.6.0
Thread model: posix
InstalledDir: /opt/homebrew/Cellar/llvm/19.1.4/bin
Configuration file: /opt/homebrew/etc/clang/arm64-apple-darwin23.cfg
System configuration file directory: /opt/homebrew/etc/clang
User configuration file directory: /Users/runner/.config/clang
"/opt/homebrew/Cellar/llvm/19.1.4/bin/clang-19" -cc1 -triple arm64-apple-macosx14.0.0 -Wundef-prefix=TARGET_OS_ -Werror=undef-prefix -Wdeprecated-objc-isa-usage -Werror=deprecated-objc-isa-usage -emit-obj -dumpdir a- -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name test_clang.cpp -mrelocation-model pic -pic-level 2 -mframe-pointer=non-leaf -ffp-contract=on -fno-rounding-math -funwind-tables=1 -fcompatibility-qualified-id-block-type-checking -fvisibility-inlines-hidden-static-local-var -fbuiltin-headers-in-system-modules -fdefine-target-os-macros -target-cpu apple-m1 -target-feature +zcm -target-feature +zcz -target-feature +v8.4a -target-feature +aes -target-feature +altnzcv -target-feature +ccdp -target-feature +complxnum -target-feature +crc -target-feature +dotprod -target-feature +fp-armv8 -target-feature +fp16fml -target-feature +fptoint -target-feature +fullfp16 -target-feature +jsconv -target-feature +lse -target-feature +neon -target-feature +pauth -target-feature +perfmon -target-feature +predres -target-feature +ras -target-feature +rcpc -target-feature +rdm -target-feature +sb -target-feature +sha2 -target-feature +sha3 -target-feature +specrestrict -target-feature +ssbs -target-abi darwinpcs -debugger-tuning=lldb -fdebug-compilation-dir=/Users/runner/work/openfhe-julia/openfhe-julia/test -target-linker-version 1115.7.3 -v -fcoverage-compilation-dir=/Users/runner/work/openfhe-julia/openfhe-julia/test -resource-dir /opt/homebrew/Cellar/llvm/19.1.4/lib/clang/19 -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk -stdlib=libc++ -internal-isystem /opt/homebrew/Cellar/llvm/19.1.4/bin/../include/c++/v1 -internal-isystem /Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/usr/local/include -internal-isystem /opt/homebrew/Cellar/llvm/19.1.4/lib/clang/19/include -internal-externc-isystem /Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/usr/include -std=gnu++17 -fdeprecated-macro -ferror-limit 19 -stack-protector 1 -fblocks -fencode-extended-block-signature -fregister-global-dtors-with-atexit -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fcxx-exceptions -fexceptions -fmax-type-align=16 -fcolor-diagnostics -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /var/folders/0w/4z5l9vds32nbkz7l22n8j6s80000gn/T/test_clang-047970.o -x c++ test_clang.cpp
clang -cc1 version 19.1.4 based upon LLVM 19.1.4 default target arm64-apple-darwin23.6.0
ignoring nonexistent directory "/Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/usr/local/include"
ignoring nonexistent directory "/Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/Library/Frameworks"
#include "..." search starts here:
#include <...> search starts here:
/opt/homebrew/Cellar/llvm/19.1.4/bin/../include/c++/v1
/opt/homebrew/Cellar/llvm/19.1.4/lib/clang/19/include
/Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/usr/include
/Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk/System/Library/Frameworks (framework directory)
End of search list.
"/usr/bin/ld" -demangle -lto_library /opt/homebrew/Cellar/llvm/19.1.4/lib/libLTO.dylib -no_deduplicate -dynamic -arch arm64 -platform_version macos 14.0.0 14.0.0 -syslibroot /Library/Developer/CommandLineTools/SDKs/MacOSX14.sdk -mllvm -enable-linkonceodr-outlining -o a.out /var/folders/0w/4z5l9vds32nbkz7l22n8j6s80000gn/T/test_clang-047970.o -lc++ -lSystem /opt/homebrew/Cellar/llvm/19.1.4/lib/clang/19/lib/darwin/libclang_rt.osx.a
Undefined symbols for architecture arm64:
"typeinfo for __int128", referenced from:
_main in test_clang-047970.o
ld: symbol(s) not found for architecture arm64
clang++: error: linker command failed with exit code 1 (use -v to see invocation)```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzEOVtv27jSv4Z5GVCQKcexH_LgxvVusS0W2Ha335tBkSObDUXqIynX6a8_GEqO01Yp9pI9pwhQe0jO_W4Zo9k7xFt2_Ypdb65knw4-3K5DRGcefjl46_VV7fXD7Rs4yCMCOuV7lzCgBgnWuHsMYGLsET4f0IHybWescXtQXiN8NukAd1a6PUinwZpaMfGKiVfgHbRS_fr-8iEdZALjjt4eMQJblOmhQ6OZWO52xqWZWDKxYouygA8HHAnJZLyD2CuFqCMTd1D3KbNFLDTS2DjwkA4IjbfWf6YDDMEHVq2Jyu9OY2McaogPbe1thMYHkEEdTEKV-oAgQ7uY5-tCZKZc4_OtC2MCHjmLskU4yK5DF0m603KxW8wLVq5ZuX6TgE5kiIO8bFE-IlmUYFJE24CJEPuu8yGRmiNIILJn8UiW0LtkWsxwIH5CO-iCZUSj6hYlE6vMqUmE1PkENZIGAkbSs4b6IeMbLDky-c4400oLn33IesSTbDuLhPvdx9dkhYquJYxpp8i4heq6AUYkh79yzURlnLK9RmDVnfExBZQtq15_dxZTMG4_dXJW93hWro1L0Erj2OAO5ZrdvGLl-tEUkIBVG5iJan69uFmuSla9Gl4CxKSJy2qtfE_X7lh1B1NeVjjZ4kjh8XnA1AcHZ4Q3m2_FLdd3T5xS-baVTo9exsTWd4mJ7cG3WAf8_Aiw9tgysa1JpG3W5hghX6sXeEzamppVmydRxLNIm73rB8DsBngTUjLAj49cvWmyiZ-6BdkbySOIS3TkZr5P5GApx5Y-BxjGMXDd_RBJpLkc7_Hs0eTJSFGS_UUG3zsNyUMfv6GZA_Frh2fVlpXrj8bas8Nnb30MMnLoryOkRjDkjCPXxkHT5yA9YojGU8g1Q8Yh3T5qaiDEyjVFaNNbO-QAaDFGucdvnLeW8cCrQjAxh_-F5cr1zyMxyGjOwsFsVcyKOYkhwx4TOVdOTlx2nUWuZfhsnKiKRVFmWQNKDa3XaOlq56M5kclcTNJa1BszZMEJEe_QWhkuUo6UB3HJ011j9n0YfL0xFp9DhEld1LOd5FY1e1au3z_EhC2o7zCDNgFV8uHhz9Ao179HDH8GDd2LTGxD7xySqMXw6Akqyvh_WTvjcz5bUV3gSs2Ap2Aogz4Vv5XKx9NsXpRFCfxjT3WIdwEbc2LV5sP6t59ef9j9-n4H_ONYrzZP7wD_qLELqGRCzX39SXETJe_JnZ88-cEdbE0iIHDdt502ASQHrk2UtUXeBETgyqIMXMbEa2x8QF5LdY9OX-6RBvgRg2kMhgxWMmh-lLZHTnk0AqeEzckGGfBdfLQBrVfZUjw7K3RGAe-M4haPaEEAb5sgW-SdN9R9sGrjvOMWZQO8aTquvEtBqsSqjXfAG-d5TkTG7Xkr0wF407vPxmmeiOvIqs0MeENJTiZTG2vSA___XloSQ3OjeW29uueUibg6oMqFkDdHE8-3jaMkGvnBaI2OxyQTMeyVtPwoA_Cm7o1NxvEDSo0hcuN4zE5OUvaUW3kzNB885XjmPpJbBB_hDFFdD6O_zB6BDcqc85h49UW10-AvU-DjspjLqQOJcRJsk_uijlNHSuluEu7bzp5cP8mWCmoKrH3qgtdTR03HZWiPy-mz2aJp7fRRIk-ZPOqtpZdTZ5-i8m5SXBtxCuyQ3O17eEed9OQBhqZ95k1AHabtEOQ0WHWT-gx6UvuxnoQepHgGXk3CO1QBqWVTk_qNsb4wK2sDQ57vVASuse73eww89S53fBtrdZ3DoO73_ElTzzXVps1UmqY2IydldM0B-afeGjnxnbLMIx9Df8sf6-hsdl3cFBXwY84CRwxyj_8GfWq0-6CQ8P21Qkstw6VwzlbATXyIwftEeN6aOsjwwMR2QynSd5m1u6HpfGscfvDeEtvvN7_Qf-9oxvq_2byI-v6ZjiRnVidtpkOl-G9UvqJgYjv278T92H2J7XE2TeCfyMHEto-ZF0q6F8L_VJRvNT-JGU_0Qb24LI-UphrEJ9U81wngTS703JrWJCAniUmqe94Fn3KzA1Tmci2jakPju8bMu9N4LnLR7N0QvlT19yYmDHxvfS0t18mHyKl15zLhySTgzd716hxKrNrMC1EQlXhvOu51GOolVbt9S-VZnU4cTwq7lPtz3nz1pZWnocpKa_aEjjJzo7z1gWsj987HZCh3bHa7n-7udj-v_3i923xc_7YVu7vtm936_buhmHsywTEbtPFWD0FbkqHnX67t6qhjJVx9_-XGCuGWnxZxWZZluSev_TCG69CU8HJ-s7opCw_8BGqyp2flemjMc3f3dXcOtYyooe-8g7dv_3h3BmtsZG8TDBnpR3272TtPAzE47_BE5nDp0r2OPem_ETiE-b9D_vJ8S30dpdQ4UH86_wtRUEIREFEGdYCYZEgRaNwcJ7avlgV0uXr97OUXzmd_GePzaWVE9ZL542VQDjPZM_YCJpbN-duT6SqvZV47TZP4aAtrYiou89TA6aBhq_OUpLGVbm8RuE1-Zwdyf0e_1tRvP_xa6AdrauDO7zTqvrOGsiZw_eBkS8NFZivHIPDOytT40O7OgZxHMxhHs_OEFh8isfUi9bcl3oGjG0Yo4-69U0i50_fJGpeHDQ-yyIuqF09r9rHm2_cvUx8H0JDHxsULHe9CKnw8FZLG8j-_aM3buh8sW5m4g4ANBnQKNTTBt-dX9G9H8yYYBxPCs3Jt81JuYIKJZWRilTejTd5cPcPUmPDP26T1ZYc8LsHHfV9eOqMell25XuZt2oyCpacZ4gjJQ0TMq-5h6B322sPflb6t9KpaySu8nd1U1Wq-LG_Kq8PtdTPHJdaIVa3EoixnolyhXGJTVbWWorwyt6IU85mYzUQ5m4tVUcprvJGVrFbVSi-WczYvsZXGFmTPwof9VV7k3c5mq0W5vLKyRhvzLwFCjMKSppkQT_ZoQrDrzVW4zWN_3e8jm5cU3fGCNZlk8Xba3D_aoOcfEPpIvv_Dnwyu-mBvDyl1kYwutkxs9yYd-rpQvr24a-awC_4TKnLsYWlJ_jqIe7wV_wkAAP__J8JGuQ">