diff options
| -rw-r--r-- | lib/Driver/ToolChains.cpp | 55 |
1 files changed, 19 insertions, 36 deletions
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp index 4da5622d96..dd84992a9c 100644 --- a/lib/Driver/ToolChains.cpp +++ b/lib/Driver/ToolChains.cpp @@ -1537,7 +1537,7 @@ public: llvm::Triple::ArchType HostArch = llvm::Triple(GccTriple).getArch(); // The library directories which may contain GCC installations. - SmallVector<StringRef, 2> CandidateLibDirs; + SmallVector<StringRef, 4> CandidateLibDirs; // The compatible GCC triples for this particular architecture. SmallVector<StringRef, 10> CandidateTriples; if (HostArch == llvm::Triple::arm || HostArch == llvm::Triple::thumb) { @@ -1600,6 +1600,11 @@ public: // specific triple is detected. CandidateTriples.push_back(D.DefaultHostTriple); + // Loop over the various components which exist and select the best GCC + // installation available. GCC installs are ranked based on age, triple + // accuracy, and architecture specificity in that order. The inverted walk + // requires testing the filesystem more times than is ideal, but shouldn't + // matter in practice as this is once on startup. static const char* GccVersions[] = { "4.6.1", "4.6.0", "4.6", "4.5.3", "4.5.2", "4.5.1", "4.5", @@ -1607,50 +1612,28 @@ public: "4.3.4", "4.3.3", "4.3.2", "4.3", "4.2.4", "4.2.3", "4.2.2", "4.2.1", "4.2", "4.1.1"}; - - // Set this as valid so we can early exit from the loops if we find - // a viable installation. - IsValid = true; - SmallVector<std::string, 8> Prefixes(D.PrefixDirs.begin(), D.PrefixDirs.end()); Prefixes.push_back(D.SysRoot + "/usr"); - // FIXME: This entire nested loop structure is broken. The structure is - // well suited to quickly pruning impossible (non-existent) sub-trees, but - // doesn't find all viable GCC installations and choose the best one. We - // should invert this, and prune the impossible subtrees bottom-up, but - // then select the best GCC installation top-down so that we prefer the - // newest GCC, the most accurate triple, and only at the end select the lib - // and prefix directories containing that installation. - for (SmallVectorImpl<std::string>::const_iterator PI = Prefixes.begin(), - PE = Prefixes.end(); - PI != PE; ++PI) { - if (!PathExists(*PI)) - continue; + IsValid = true; + for (unsigned i = 0; i < llvm::array_lengthof(GccVersions); ++i) { + for (unsigned j = 0, je = CandidateTriples.size(); j < je; ++j) { + GccTriple = CandidateTriples[j]; + for (unsigned k = 0, ke = CandidateLibDirs.size(); k < ke; ++k) { + const std::string LibDir = CandidateLibDirs[k].str() + "/"; + for (unsigned l = 0, le = Prefixes.size(); l < le; ++l) { + if (!PathExists(Prefixes[l])) + continue; - // First finds the 'prefix' which exists beneath the system root. Second, - // finds the first triple which exists beneath that prefix. - StringRef DetectedGccPrefix, DetectedGccTriple; - for (unsigned i = 0, ie = CandidateLibDirs.size(); i < ie; ++i) { - const std::string LibDir = *PI + CandidateLibDirs[i].str(); - if (!PathExists(LibDir)) - continue; - - for (unsigned j = 0, je = CandidateTriples.size(); j < je; ++j) { - GccTriple = CandidateTriples[j]; - const std::string TripleDir = LibDir + "/" + GccTriple; - if (!PathExists(TripleDir)) - continue; - - for (unsigned k = 0; k < llvm::array_lengthof(GccVersions); ++k) { - GccInstallPath = TripleDir + "/" + GccVersions[k]; + const std::string TripleDir = Prefixes[l] + LibDir + GccTriple; + GccInstallPath = TripleDir + "/" + GccVersions[i]; GccParentLibPath = GccInstallPath + "/../../.."; if (PathExists(GccInstallPath + "/crtbegin.o")) return; // Try an install directory with an extra triple in it. GccInstallPath = - TripleDir + "/gcc/" + GccTriple + "/" + GccVersions[k]; + TripleDir + "/gcc/" + GccTriple + "/" + GccVersions[i]; GccParentLibPath = GccInstallPath + "/../../../.."; if (PathExists(GccInstallPath + "/crtbegin.o")) return; @@ -1660,7 +1643,7 @@ public: // Ubuntu 11.04 uses an unusual path. GccInstallPath = - TripleDir + "/gcc/i686-linux-gnu/" + GccVersions[k]; + TripleDir + "/gcc/i686-linux-gnu/" + GccVersions[i]; GccParentLibPath = GccInstallPath + "/../../../.."; if (PathExists(GccInstallPath + "/crtbegin.o")) return; |