build: qt build broken on aarch64 macOS #34951

1. 
   fanquake commented at 1:30 am on March 30, 2026: member

    0# clang --version
    1Apple clang version 21.0.0 (clang-2100.0.123.102)
    2
    3make -C depends
    4<snip>
    5In file included from /bitcoin/depends/work/build/aarch64-apple-darwin25.3.0/qt/6.8.3-130fac6dd57/qtbase/include/QtCore/qyieldcpu.h:1:
    6/bitcoin/depends/work/build/aarch64-apple-darwin25.3.0/qt/6.8.3-130fac6dd57/qtbase/src/corelib/thread/qyieldcpu.h:35:5: error: implicitly declaring library function '__yield' with type 'void ()' [-Werror,-Wimplicit-function-declaration]
    7   35 |     __yield();              // Generic
    8      |     ^
    9/bitcoin/depends/work/build/aarch64-apple-darwin25.3.0/qt/6.8.3-130fac6dd57/qtbase/src/corelib/thread/qyieldcpu.h:35:5: note: include the header <arm_acle.h> or explicitly provide a declaration for '__yield'
   101 error generated.
   

2. hebasto added the label macOS on Mar 30, 2026
3. hebasto added the label Build system on Mar 30, 2026
4. 
   hebasto commented at 10:57 am on March 30, 2026: member

   0# clang --version
   1Apple clang version 21.0.0 (clang-2100.0.123.102)
   

   A note for myself: this Apple clang version is part of the recent Xcode 26.4 update.

5. fanquake added this to the milestone 31.0 on Mar 30, 2026

Contributors
fanquake hebasto

Labels
macOS Build system

Milestone
31.0