Clang attempts to guess file names based on the OS and distro (yes!), but unfortunately, that doesn't work for us. This patch makes it easy to insert libc's $libdir so that Clang passes the correct absolute file name of crt1.o etc. to 'ld'. It also disables all the distro-specific stuff and removes the hard-coded FHS directory names to make sure Clang also works on foreign distros. diff --git a/lib/Driver/Distro.cpp b/lib/Driver/Distro.cpp index f2a3074d..536db89c 100644 --- a/lib/Driver/Distro.cpp +++ b/lib/Driver/Distro.cpp @@ -18,6 +18,10 @@ using namespace clang::driver; using namespace clang; static Distro::DistroType DetectDistro(llvm::vfs::FileSystem &VFS) { + // The compiler should always behave the same, even when used via Guix on a + // foreign distro. + return Distro::UnknownDistro; + llvm::ErrorOr> File = VFS.getBufferForFile("/etc/lsb-release"); if (File) { diff --git a/lib/Driver/ToolChains/Cuda.cpp b/lib/Driver/ToolChains/Cuda.cpp index 96f8c513..64fd7a26 100644 --- a/lib/Driver/ToolChains/Cuda.cpp +++ b/lib/Driver/ToolChains/Cuda.cpp @@ -69,6 +69,9 @@ CudaInstallationDetector::CudaInstallationDetector( const Driver &D, const llvm::Triple &HostTriple, const llvm::opt::ArgList &Args) : D(D) { + // Don't look for CUDA in /usr. + return; + struct Candidate { std::string Path; bool StrictChecking; diff --git a/lib/Driver/ToolChains/Linux.cpp b/lib/Driver/ToolChains/Linux.cpp index 7f59bc77..67d8ce22 100644 --- a/lib/Driver/ToolChains/Linux.cpp +++ b/lib/Driver/ToolChains/Linux.cpp @@ -240,6 +240,9 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args) .str()); } + // Comment out the distro-specific tweaks so that they don't bite when + // using Guix on a foreign distro. +#if 0 Distro Distro(D.getVFS()); if (Distro.IsAlpineLinux() || Triple.isAndroid()) { @@ -306,6 +309,7 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args) if (IsAndroid || Distro.IsOpenSUSE()) ExtraOpts.push_back("--enable-new-dtags"); +#endif // The selection of paths to try here is designed to match the patterns which // the GCC driver itself uses, as this is part of the GCC-compatible driver. @@ -369,6 +373,7 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args) } } +#if 0 // Similar to the logic for GCC above, if we currently running Clang inside // of the requested system root, add its parent library paths to // those searched. @@ -414,6 +419,8 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args) // Try walking via the GCC triple path in case of biarch or multiarch GCC // installations with strange symlinks. if (GCCInstallation.isValid()) { + // The following code would end up adding things like + // "/usr/lib/x86_64-unknown-linux-gnu/../../lib64" to the search path. addPathIfExists(D, SysRoot + "/usr/lib/" + GCCInstallation.getTriple().str() + "/../../" + OSLibDir, @@ -449,9 +456,14 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args) // directory ('Dir' below) or the ResourceDir. if (StringRef(D.Dir).startswith(SysRoot)) addPathIfExists(D, D.Dir + "/../lib", Paths); +#endif + + // Add libc's lib/ directory to the search path, so that crt1.o, crti.o, + // and friends can be found. + addPathIfExists(D, "@GLIBC_LIBDIR@", Paths); - addPathIfExists(D, SysRoot + "/lib", Paths); - addPathIfExists(D, SysRoot + "/usr/lib", Paths); + // Add GCC's lib/ directory so libstdc++.so can be found. + addPathIfExists(D, GCCInstallation.getParentLibPath(), Paths); } ToolChain::CXXStdlibType Linux::GetDefaultCXXStdlibType() const {