https://github.com/aokblast created https://github.com/llvm/llvm-project/pull/181972
On Linux, the system libgcc may act as the compiler runtime, and Clang provides -rtlib=compiler-rt to switch implementations. FreeBSD ships libcompiler_rt.a (LLVM’s builtins) in the base system, with libgcc.a as a symlink to it. These libraries are linked via -L and -lgcc. An interesting detail is that even if the Clang resource directory (llvm-xx/lib/clang/xx) appears before the system path in the search order, it is still not used. This is because the linker looks for libgcc.a rather than libclang_rt.builtins.a. Since FreeBSD does not currently support -rtlib, honor the system libgcc by hardcoding its path. Detect and handle cases where a custom compiler-rt is injected via -L as an override workaround. >From 2680016317d4b90dea5061e93c76e83015e172ba Mon Sep 17 00:00:00 2001 From: ShengYi Hung <[email protected]> Date: Wed, 18 Feb 2026 15:04:48 +0800 Subject: [PATCH] [Toolchains][FreeBSD] Honor system libgcc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On Linux, the system libgcc may act as the compiler runtime, and Clang provides -rtlib=compiler-rt to switch implementations. FreeBSD ships libcompiler_rt.a (LLVM’s builtins) in the base system, with libgcc.a as a symlink to it. These libraries are linked via -L and -lgcc. An interesting detail is that even if the Clang resource directory (llvm-xx/lib/clang/xx) appears before the system path in the search order, it is still not used. This is because the linker looks for libgcc.a rather than libclang_rt.builtins.a. Since FreeBSD does not currently support -rtlib, honor the system libgcc by hardcoding its path. Detect and handle cases where a custom compiler-rt is injected via -L as an override workaround. --- clang/lib/Driver/ToolChains/FreeBSD.cpp | 17 +++++++++++++++++ clang/lib/Driver/ToolChains/FreeBSD.h | 2 ++ clang/test/Driver/freebsd.cpp | 4 ++++ 3 files changed, 23 insertions(+) diff --git a/clang/lib/Driver/ToolChains/FreeBSD.cpp b/clang/lib/Driver/ToolChains/FreeBSD.cpp index cf6ad385d949a..0d0142bdd5968 100644 --- a/clang/lib/Driver/ToolChains/FreeBSD.cpp +++ b/clang/lib/Driver/ToolChains/FreeBSD.cpp @@ -511,3 +511,20 @@ SanitizerMask FreeBSD::getSupportedSanitizers() const { } return Res; } + +std::string FreeBSD::getCompilerRT(const llvm::opt::ArgList &Args, + StringRef Component, FileType Type, + bool IsFortran) const { + if (Component == "builtins") { + std::string DetectedPath = + ToolChain::getCompilerRT(Args, Component, Type, IsFortran); + if (getVFS().exists(DetectedPath)) + return DetectedPath; + SmallString<128> Path(getDriver().SysRoot); + llvm::sys::path::append(Path, "/usr/lib/libgcc.a"); + if (getVFS().exists(Path)) + return std::string(Path); + return DetectedPath; + } + return ToolChain::getCompilerRT(Args, Component, Type, IsFortran); +} diff --git a/clang/lib/Driver/ToolChains/FreeBSD.h b/clang/lib/Driver/ToolChains/FreeBSD.h index 7d090ba682b30..51473597a5703 100644 --- a/clang/lib/Driver/ToolChains/FreeBSD.h +++ b/clang/lib/Driver/ToolChains/FreeBSD.h @@ -91,6 +91,8 @@ class LLVM_LIBRARY_VISIBILITY FreeBSD : public Generic_ELF { // Until dtrace (via CTF) and LLDB can deal with distributed debug info, // FreeBSD defaults to standalone/full debug info. bool GetDefaultStandaloneDebug() const override { return true; } + std::string getCompilerRT(const llvm::opt::ArgList &Args, StringRef Component, + FileType Type, bool IsFortran) const override; protected: Tool *buildAssembler() const override; diff --git a/clang/test/Driver/freebsd.cpp b/clang/test/Driver/freebsd.cpp index e2f76cd013f7f..c0619a8da39a5 100644 --- a/clang/test/Driver/freebsd.cpp +++ b/clang/test/Driver/freebsd.cpp @@ -9,6 +9,10 @@ // CHECK-DEFAULT: "-lc++" "-lm" // CHECK-STDLIBCXX: "-lstdc++" "-lm" +// RUN: %clangxx %s --print-libgcc-file-name --target=amd64-unknown-freebsd 2>&1 \ +// RUN: | FileCheck --check-prefix=CHECK-BUILTIN %s +// CHECK-BUILTIN: /usr/lib/libgcc.a + // RUN: %clangxx %s -### -pg --target=amd64-unknown-freebsd -stdlib=platform 2>&1 \ // RUN: | FileCheck --check-prefix=CHECK-PG-DEFAULT %s // RUN: %clangxx %s -### -pg --target=amd64-unknown-freebsd14.0 -stdlib=platform 2>&1 \ _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
