r188400 - Enhance the clang -v gcc debug printing to skip obviously bad and duplicate paths.

[Benjamin Kramer]

On 14.08.2013, at 21:32, Eli Friedman <eli.friedman at gmail.com> wrote:

> On Wed, Aug 14, 2013 at 11:38 AM, Benjamin Kramer <benny.kra at googlemail.com> wrote:
> Author: d0k
> Date: Wed Aug 14 13:38:51 2013
> New Revision: 188400
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=188400&view=rev
> Log:
> Enhance the clang -v gcc debug printing to skip obviously bad and duplicate paths.
> 
> Otherwise it lists all files (e.g. shared libraries) that happen to be in the
> same paths the GCC installations usually reside in.
> 
> On a x86_64 Debian 7 system with i386 multilibs.
> before: clang -v 2>&1|wc -l
>         3059
> after:  clang -v 2>&1|wc -l
>         10
> 
> Testcase?

r188405.

> Modified:
>     cfe/trunk/lib/Driver/ToolChains.cpp
>     cfe/trunk/lib/Driver/ToolChains.h
> 
> Modified: cfe/trunk/lib/Driver/ToolChains.cpp
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains.cpp?rev=188400&r1=188399&r2=188400&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Driver/ToolChains.cpp (original)
> +++ cfe/trunk/lib/Driver/ToolChains.cpp Wed Aug 14 13:38:51 2013
> @@ -1052,7 +1052,7 @@ Generic_GCC::GCCInstallationDetector::GC
>  }
> 
>  void Generic_GCC::GCCInstallationDetector::print(raw_ostream &OS) const {
> -  for (SmallVectorImpl<std::string>::const_iterator
> +  for (std::set<std::string>::const_iterator
>             I = CandidateGCCInstallPaths.begin(),
>             E = CandidateGCCInstallPaths.end();
>         I != E; ++I)
> @@ -1395,9 +1395,11 @@ void Generic_GCC::GCCInstallationDetecto
>      llvm::error_code EC;
>      for (llvm::sys::fs::directory_iterator LI(LibDir + LibSuffix, EC), LE;
>           !EC && LI != LE; LI = LI.increment(EC)) {
> -      CandidateGCCInstallPaths.push_back(LI->path());
>        StringRef VersionText = llvm::sys::path::filename(LI->path());
>        GCCVersion CandidateVersion = GCCVersion::Parse(VersionText);
> +      if (CandidateVersion.Major != -1) // Filter obviously bad entries.
> +        if (!CandidateGCCInstallPaths.insert(LI->path()).second)
> +          continue; // Saw this path before; no need to look at it again.
>        if (CandidateVersion.isOlderThan(4, 1, 1))
>          continue;
>        if (CandidateVersion <= Version)
> 
> Modified: cfe/trunk/lib/Driver/ToolChains.h
> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/ToolChains.h?rev=188400&r1=188399&r2=188400&view=diff
> ==============================================================================
> --- cfe/trunk/lib/Driver/ToolChains.h (original)
> +++ cfe/trunk/lib/Driver/ToolChains.h Wed Aug 14 13:38:51 2013
> @@ -16,8 +16,8 @@
>  #include "clang/Driver/ToolChain.h"
>  #include "llvm/ADT/DenseMap.h"
>  #include "llvm/Support/Compiler.h"
> -
>  #include <vector>
> +#include <set>
> 
>  namespace clang {
>  namespace driver {
> @@ -84,7 +84,7 @@ protected:
> 
>      // We retain the list of install paths that were considered and rejected in
>      // order to print out detailed information in verbose mode.
> -    SmallVector<std::string, 4> CandidateGCCInstallPaths;
> +    std::set<std::string> CandidateGCCInstallPaths;
> 
> 
> Maybe consider using StringSet?

This isn't performance critical. As a bonus we get deterministic output, this set goes directly to stderr.

- Ben

> 
> -Eli