I tested the upstream patch with clang 19, and it worked just fine here. I pushed the patch to salsa.
diff --git a/debian/patches/0002-clang-21.patch b/debian/patches/0002-clang-21.patch new file mode 100644 index 00000000..f8e7eb04 --- /dev/null +++ b/debian/patches/0002-clang-21.patch @@ -0,0 +1,46 @@ +commit 8c5c96ad3beeed2fa827017f451a952306826974 +Author: yonghong-song <[email protected]> +Date: Mon Jul 14 20:21:59 2025 -0700 +Origin: https://github.com/iovisor/bcc/commit/8c5c96ad3beeed2fa827017f451a952306826974 +Bug-Debian: https://bugs.debian.org/1122606 +Forwarded: not-needed +Last-Update: 2025-12-20 + + Fix a build failure with clang21 (#5369) + + The build error message: + src/cc/frontends/clang/loader.cc:400:73: error: no matching function for + call to ‘clang::TextDiagnosticPrinter::TextDiagnosticPrinter( + llvm::raw_fd_ostream&, clang::DiagnosticOptions*)’ + 400 | auto diag_client = new TextDiagnosticPrinter(llvm::errs(), &*diag_opts); + | ^ + The llvm commit + https://github.com/llvm/llvm-project/pull/139584 + caused the build failure. + + Adjust the code properly and the error is fixed. + +diff --git a/src/cc/frontends/clang/loader.cc b/src/cc/frontends/clang/loader.cc +index 07dc9d6a..6f8387aa 100644 +--- a/src/cc/frontends/clang/loader.cc ++++ b/src/cc/frontends/clang/loader.cc +@@ -396,11 +396,19 @@ int ClangLoader::do_compile( + flags_cstr_rem.end()); + + // set up the error reporting class ++#if LLVM_VERSION_MAJOR >= 21 ++ DiagnosticOptions diag_opts; ++ auto diag_client = new TextDiagnosticPrinter(llvm::errs(), diag_opts); ++ ++ IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs()); ++ DiagnosticsEngine diags(DiagID, diag_opts, diag_client); ++#else + IntrusiveRefCntPtr<DiagnosticOptions> diag_opts(new DiagnosticOptions()); + auto diag_client = new TextDiagnosticPrinter(llvm::errs(), &*diag_opts); + + IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs()); + DiagnosticsEngine diags(DiagID, &*diag_opts, diag_client); ++#endif + + // set up the command line argument wrapper + diff --git a/debian/patches/series b/debian/patches/series index 21b3c377..6a302de5 100644 --- a/debian/patches/series +++ b/debian/patches/series @@ -3,3 +3,4 @@ fix-install-path.patch 2002_fix_netqtop.c_path.patch 2003-libbpf-tools-debian.patch 0001-Cleanup-existing-temporary-kernel-headers-path.patch +0002-clang-21.patch -- Happy hacking Petter Reinholdtsen
