[c-index-test] Use correct executable path to discover resource directory.

Driver builds resource directory path based on provided executable path.
Instead of string "clang" use actual executable path.

rdar://problem/42699514

Reviewers: nathawes, akyrtzi, bob.wilson

Reviewed By: akyrtzi

Subscribers: dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D50160

llvm-svn: 338741

clang/tools/c-index-test/core_main.cpp

@@ -20,6 +20,7 @@
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Serialization/ASTReader.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/PrettyStackTrace.h"
@@ -202,11 +203,11 @@ static void dumpModuleFileInputs(serialization::ModuleFile &Mod,
   });
 }
 
-static bool printSourceSymbols(ArrayRef<const char *> Args,
-                               bool dumpModuleImports,
-                               bool indexLocals) {
+static bool printSourceSymbols(const char *Executable,
+                               ArrayRef<const char *> Args,
+                               bool dumpModuleImports, bool indexLocals) {
   SmallVector<const char *, 4> ArgsWithProgName;
-  ArgsWithProgName.push_back("clang");
+  ArgsWithProgName.push_back(Executable);
   ArgsWithProgName.append(Args.begin(), Args.end());
   IntrusiveRefCntPtr<DiagnosticsEngine>
     Diags(CompilerInstance::createDiagnostics(new DiagnosticOptions));
@@ -314,6 +315,8 @@ static void printSymbolNameAndUSR(const Decl *D, ASTContext &Ctx,
 int indextest_core_main(int argc, const char **argv) {
   sys::PrintStackTraceOnErrorSignal(argv[0]);
   PrettyStackTraceProgram X(argc, argv);
+  void *MainAddr = (void*) (intptr_t) indextest_core_main;
+  std::string Executable = llvm::sys::fs::getMainExecutable(argv[0], MainAddr);
 
   assert(argv[1] == StringRef("core"));
   ++argv;
@@ -343,7 +346,9 @@ int indextest_core_main(int argc, const char **argv) {
       errs() << "error: missing compiler args; pass '-- <compiler arguments>'\n";
       return 1;
     }
-    return printSourceSymbols(CompArgs, options::DumpModuleImports, options::IncludeLocals);
+    return printSourceSymbols(Executable.c_str(), CompArgs,
+                              options::DumpModuleImports,
+                              options::IncludeLocals);
   }
 
   return 0;