Unable to fuzz in local on MacOS 15.4.1 #33667

rkrux commented at 11:38 AM on October 21, 2025: contributor

Reproduction steps as per libfuzzer:

$ brew install llvm lld
$ cmake --preset=libfuzzer \
   -DCMAKE_C_COMPILER="$(brew --prefix llvm)/bin/clang" \
   -DCMAKE_CXX_COMPILER="$(brew --prefix llvm)/bin/clang++" \
   -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld"
$ cmake --build build_fuzz

<details open> <summary> Getting the following error instead on the last step: </summary>

[ 99%] Building CXX object src/test/fuzz/CMakeFiles/fuzz.dir/__/__/wallet/test/fuzz/spend.cpp.o
[100%] Building CXX object src/test/fuzz/CMakeFiles/fuzz.dir/__/__/wallet/test/fuzz/scriptpubkeyman.cpp.o
[100%] Building CXX object src/test/fuzz/CMakeFiles/fuzz.dir/__/__/wallet/test/fuzz/wallet_bdb_parser.cpp.o
[100%] Linking CXX executable ../../../bin/fuzz
ld64.lld: error: undefined symbol: std::__1::__hash_memory(void const*, unsigned long)
>>> referenced by /Users/rkrux/projects/rkrux/bitcoin/build_fuzz/src/util/./support/lockedpool.cpp
>>>               ../../../lib/libbitcoin_util.a(lockedpool.cpp.o):(symbol std::__1::pair<std::__1::__hash_iterator<std::__1::__hash_node<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, void*>*>, bool> std::__1::__hash_table<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::__unordered_map_hasher<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::hash<void*>, std::__1::equal_to<void*>, true>, std::__1::__unordered_map_equal<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::equal_to<void*>, std::__1::hash<void*>, true>, std::__1::allocator<std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>>>::__emplace_unique_key_args<void*, void*&, std::__1::__map_iterator<std::__1::__tree_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>&>(void* const&, void*&, std::__1::__map_iterator<std::__1::__tree_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>&)+0x100)
>>> referenced by /Users/rkrux/projects/rkrux/bitcoin/build_fuzz/src/util/./support/lockedpool.cpp
>>>               ../../../lib/libbitcoin_util.a(lockedpool.cpp.o):(symbol std::__1::unique_ptr<std::__1::__hash_node<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, void*>, std::__1::__hash_node_destructor<std::__1::allocator<std::__1::__hash_node<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, void*>>>> std::__1::__hash_table<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::__unordered_map_hasher<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::hash<void*>, std::__1::equal_to<void*>, true>, std::__1::__unordered_map_equal<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::equal_to<void*>, std::__1::hash<void*>, true>, std::__1::allocator<std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>>>::__construct_node<char*, std::__1::__map_iterator<std::__1::__tree_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>&>(char*&&, std::__1::__map_iterator<std::__1::__tree_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>&)+0x2d1)
>>> referenced by /Users/rkrux/projects/rkrux/bitcoin/build_fuzz/src/util/./support/lockedpool.cpp
>>>               ../../../lib/libbitcoin_util.a(lockedpool.cpp.o):(symbol std::__1::__hash_table<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::__unordered_map_hasher<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::hash<void*>, std::__1::equal_to<void*>, true>, std::__1::__unordered_map_equal<void*, std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, std::__1::equal_to<void*>, std::__1::hash<void*>, true>, std::__1::allocator<std::__1::pair<void* const, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>>>::__node_insert_unique(std::__1::__hash_node<std::__1::__hash_value_type<void*, std::__1::__map_const_iterator<std::__1::__tree_const_iterator<std::__1::__value_type<unsigned long, void*>, std::__1::__tree_node<std::__1::__value_type<unsigned long, void*>, void*>*, long>>>, void*>*)+0x116)
>>> referenced 19 more times
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [bin/fuzz] Error 1
make[1]: *** [src/test/fuzz/CMakeFiles/fuzz.dir/all] Error 2
make: *** [all] Error 2

</details>

maflcko added the label Tests on Oct 21, 2025

maflcko added the label Docs on Oct 21, 2025

maflcko added the label macOS on Oct 21, 2025

maflcko commented at 12:59 PM on October 21, 2025: member

There are some prior issues/pulls/discussions:

Though, this one seems to be a new link-time error.

fanquake commented at 10:28 AM on October 25, 2025: member

Looks like this could be https://github.com/Homebrew/homebrew-core/issues/235411.

maflcko commented at 11:06 AM on October 25, 2025: member

So I guess this can be fixed by using the homebrew libc++?

fanquake added the label Fuzzing on Oct 30, 2025

maflcko commented at 2:41 PM on November 21, 2025: member

Closing for now. If someone finds this to be working at some point, they are welcome to add docs for it. In the meantime, please use libfuzzer-nosan, or other stuff, mentioned in https://github.com/bitcoin/bitcoin/pull/33921

maflcko closed this on Nov 21, 2025