gnu/packages/patches/clang-9.0-libc-search-path.patch

   1 Clang attempts to guess file names based on the OS and distro (yes!),
   2 but unfortunately, that doesn't work for us.
   3
   4 This patch makes it easy to insert libc's $libdir so that Clang passes the
   5 correct absolute file name of crt1.o etc. to 'ld'.  It also disables all
   6 the distro-specific stuff and removes the hard-coded FHS directory names
   7 to make sure Clang also works on non-GuixSD systems.
   8
   9 diff --git a/lib/Driver/ToolChains/Linux.cpp b/lib/Driver/ToolChains/Linux.cpp
  10 --- a/lib/Driver/ToolChains/Linux.cpp
  11 +++ b/lib/Driver/ToolChains/Linux.cpp
  12 @@ -240,6 +240,9 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  13                           .str());
  14    }
  15
  16 +// Comment out the distro-specific tweaks so that they don't bite when
  17 +// using Guix on a foreign distro.
  18 +#if 0
  19    Distro Distro(D.getVFS());
  20
  21    if (Distro.IsAlpineLinux() || Triple.isAndroid()) {
  22 @@ -306,6 +309,7 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  23
  24    if (IsAndroid || Distro.IsOpenSUSE())
  25      ExtraOpts.push_back("--enable-new-dtags");
  26 +#endif
  27
  28    // The selection of paths to try here is designed to match the patterns which
  29    // the GCC driver itself uses, as this is part of the GCC-compatible driver.
  30 @@ -363,7 +367,7 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  31      // the cross. Note that GCC does include some of these directories in some
  32      // configurations but this seems somewhere between questionable and simply
  33      // a bug.
  34 -    if (StringRef(LibPath).startswith(SysRoot)) {
  35 +    if (0) {
  36        addPathIfExists(D, LibPath + "/" + MultiarchTriple, Paths);
  37        addPathIfExists(D, LibPath + "/../" + OSLibDir, Paths);
  38      }
  39 @@ -382,6 +386,8 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  40    addPathIfExists(D, SysRoot + "/lib/" + MultiarchTriple, Paths);
  41    addPathIfExists(D, SysRoot + "/lib/../" + OSLibDir, Paths);
  42
  43 +// This requires the commented distro tweaks above.
  44 +#if 0
  45    if (IsAndroid) {
  46      // Android sysroots contain a library directory for each supported OS
  47      // version as well as some unversioned libraries in the usual multiarch
  48 @@ -410,10 +416,15 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  49      addPathIfExists(D, SysRoot + "/" + OSLibDir + "/" + ABIName, Paths);
  50      addPathIfExists(D, SysRoot + "/usr/" + OSLibDir + "/" + ABIName, Paths);
  51    }
  52 +#endif
  53
  54    // Try walking via the GCC triple path in case of biarch or multiarch GCC
  55    // installations with strange symlinks.
  56    if (GCCInstallation.isValid()) {
  57 +
  58 +// The following code would end up adding things like
  59 +// "/usr/lib/x86_64-unknown-linux-gnu/../../lib64" to the search path.
  60 +#if 0
  61      addPathIfExists(D,
  62                      SysRoot + "/usr/lib/" + GCCInstallation.getTriple().str() +
  63                          "/../../" + OSLibDir,
  64 @@ -426,6 +437,7 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  65                               BiarchSibling.gccSuffix(),
  66                        Paths);
  67      }
  68 +#endif
  69
  70      // See comments above on the multilib variant for details of why this is
  71      // included even from outside the sysroot.
  72 @@ -450,8 +462,9 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
  73    if (StringRef(D.Dir).startswith(SysRoot))
  74      addPathIfExists(D, D.Dir + "/../lib", Paths);
  75
  76 -  addPathIfExists(D, SysRoot + "/lib", Paths);
  77 -  addPathIfExists(D, SysRoot + "/usr/lib", Paths);
  78 +  // Add libc's lib/ directory to the search path, so that crt1.o, crti.o,
  79 +  // and friends can be found.
  80 +  addPathIfExists(D, "@GLIBC_LIBDIR@", Paths);
  81  }
  82
  83  ToolChain::CXXStdlibType Linux::GetDefaultCXXStdlibType() const {