gnu: Remove clang-8.

* gnu/packages/llvm.scm (clang-8): Delete variable.
* gnu/packages/patches/clang-8.0-libc-search-path.patch: Remove file.
* gnu/local.mk (dist_patch_DATA): Unregister file.

Change-Id: I46b47cb9847ef82a44817021c097b240547c3073

gnu/local.mk

@@ -1114,7 +1114,6 @@ dist_patch_DATA =						\
   %D%/packages/patches/clang-3.5-libsanitizer-ustat-fix.patch	\
   %D%/packages/patches/clang-3.8-libc-search-path.patch		\
   %D%/packages/patches/clang-6.0-libc-search-path.patch		\
-  %D%/packages/patches/clang-8.0-libc-search-path.patch		\
   %D%/packages/patches/clang-10.0-libc-search-path.patch	\
   %D%/packages/patches/clang-11.0-libc-search-path.patch	\
   %D%/packages/patches/clang-12.0-libc-search-path.patch	\

gnu/packages/llvm.scm

@@ -1158,12 +1158,6 @@ Library.")
    '("clang-runtime-9-libsanitizer-mode-field.patch"
      "clang-runtime-9-glibc-2.36-compat.patch")))
 
-(define-public clang-8
-  (clang-from-llvm llvm-8 clang-runtime-8
-                   "0ihnbdl058gvl2wdy45p5am55bq8ifx8m9mhcsgj9ax8yxlzvvvh"
-                   #:legacy-build-shared-libs? #t
-                   #:patches '("clang-8.0-libc-search-path.patch")))
-
 (define-public llvm-6
   (package
     (inherit llvm-10)

gnu/packages/patches/clang-8.0-libc-search-path.patch

@@ -1,94 +0,0 @@
-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 396d0bee..90e06613 100644
---- a/lib/Driver/Distro.cpp
-+++ b/lib/Driver/Distro.cpp
-@@ -19,6 +19,10 @@ 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<std::unique_ptr<llvm::MemoryBuffer>> File =
-       VFS.getBufferForFile("/etc/lsb-release");
-   if (File) {
-diff --git a/lib/Driver/ToolChains/Cuda.cpp b/lib/Driver/ToolChains/Cuda.cpp
-index 57b8d434..57339f1a 100644
---- a/lib/Driver/ToolChains/Cuda.cpp
-+++ b/lib/Driver/ToolChains/Cuda.cpp
-@@ -68,6 +68,9 @@ 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 65ab9b2d..5ed28e0a 100644
---- a/lib/Driver/ToolChains/Linux.cpp
-+++ b/lib/Driver/ToolChains/Linux.cpp
-@@ -233,7 +233,9 @@ Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
-   PPaths.push_back(Twine(GCCInstallation.getParentLibPath() + "/../" +
-                          GCCInstallation.getTriple().str() + "/bin")
-                        .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()) {
-@@ -304,6 +306,7 @@ 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.
-@@ -366,6 +369,7 @@ 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.
-@@ -411,6 +415,8 @@ 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,
-@@ -446,9 +452,14 @@ 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 {