Fix one of the (larger) FIXMEs where we were misusing the Driver's idea

of the target triple to stand in for the "host" triple.

Thanks to a great conversation with Richard Smith, I'm now much more
confident in how this is proceeding. In all of the places where we
currently reason about the "host" architecture or triple, what we really
want to reason about in the detected GCC installation architecture or
triple, and the ways in which that differs from the target. When we find
a GCC installation with a different triple from our target *but capable
of targeting our target* through an option such as '-m64', we want to
detect *that* case and change the paths within the GCC installation (and
libstdc++ installation) to reflect this difference.

This patch makes one function do this correctly. Subsequent commits will
hoist the logic used here into the GCCInstallation utility, and then
reuse it through the rest of the toolchains to fix the remaining places
where this is currently happening.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148852 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index a2a4748334f2e458d435b435a86725275b45f568..b62be8bfdb3607c7ca69a6bf9915055986939342 100644 (file)
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -1897,8 +1897,7 @@ static std::string getMultiarchTriple(const llvm::Triple TargetTriple,
 
 Linux::Linux(const HostInfo &Host, const llvm::Triple &Triple)
   : Generic_ELF(Host, Triple) {
-  // FIXME: This is using the Driver's target triple to emulate the host triple!
-  llvm::Triple::ArchType Arch = getDriver().TargetTriple.getArch();
+  llvm::Triple::ArchType Arch = Triple.getArch();
   const std::string &SysRoot = getDriver().SysRoot;
 
   // OpenSuse stores the linker with the compiler, add that to the search
@@ -1961,28 +1960,33 @@ Linux::Linux(const HostInfo &Host, const llvm::Triple &Triple)
   // possible permutations of these directories, and seeing which ones it added
   // to the link paths.
   path_list &Paths = getFilePaths();
-  const bool Is32Bits = (getArch() == llvm::Triple::x86 ||
-                         getArch() == llvm::Triple::mips ||
-                         getArch() == llvm::Triple::mipsel ||
-                         getArch() == llvm::Triple::ppc);
-
-  StringRef Suffix32;
-  StringRef Suffix64;
-  if (Arch == llvm::Triple::x86_64 || Arch == llvm::Triple::ppc64) {
-    Suffix32 = "/32";
-    Suffix64 = "";
-  } else {
-    Suffix32 = "";
-    Suffix64 = "/64";
-  }
-  const std::string Suffix = Is32Bits ? Suffix32 : Suffix64;
+
+  const bool Is32Bits = (Arch == llvm::Triple::x86 ||
+                         Arch == llvm::Triple::mips ||
+                         Arch == llvm::Triple::mipsel ||
+                         Arch == llvm::Triple::ppc);
+
   const std::string Multilib = Is32Bits ? "lib32" : "lib64";
   const std::string MultiarchTriple = getMultiarchTriple(Triple, SysRoot);
 
   // Add the multilib suffixed paths where they are available.
+  bool SuffixedGCCInstallation = false;
   if (GCCInstallation.isValid()) {
-    const std::string &LibPath = GCCInstallation.getParentLibPath();
+    StringRef Suffix32;
+    StringRef Suffix64;
     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
+    if (GCCTriple.getArch() == llvm::Triple::x86_64 ||
+        GCCTriple.getArch() == llvm::Triple::ppc64) {
+      Suffix32 = "/32";
+      Suffix64 = "";
+    } else {
+      Suffix32 = "";
+      Suffix64 = "/64";
+    }
+    const std::string Suffix = Is32Bits ? Suffix32 : Suffix64;
+    SuffixedGCCInstallation = !Suffix.empty();
+
+    const std::string &LibPath = GCCInstallation.getParentLibPath();
     addPathIfExists(GCCInstallation.getInstallPath() + Suffix, Paths);
     addPathIfExists(LibPath + "/../" + GCCTriple.str() + "/lib/../" + Multilib,
                     Paths);
@@ -2004,7 +2008,7 @@ Linux::Linux(const HostInfo &Host, const llvm::Triple &Triple)
   if (GCCInstallation.isValid()) {
     const std::string &LibPath = GCCInstallation.getParentLibPath();
     const llvm::Triple &GCCTriple = GCCInstallation.getTriple();
-    if (!Suffix.empty())
+    if (SuffixedGCCInstallation)
       addPathIfExists(GCCInstallation.getInstallPath(), Paths);
     addPathIfExists(LibPath + "/../" + GCCTriple.str() + "/lib", Paths);
     addPathIfExists(LibPath, Paths);