diff --git a/clang/lib/Driver/ToolChains/AIX.cpp b/clang/lib/Driver/ToolChains/AIX.cpp
--- a/clang/lib/Driver/ToolChains/AIX.cpp
+++ b/clang/lib/Driver/ToolChains/AIX.cpp
@@ -243,6 +243,25 @@
   if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) {
     AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
 
+    // Add OpenMP runtime if -fopenmp is specified.
+    if (Args.hasFlag(options::OPT_fopenmp, options::OPT_fopenmp_EQ,
+                     options::OPT_fno_openmp, false)) {
+      switch (ToolChain.getDriver().getOpenMPRuntime(Args)) {
+      case Driver::OMPRT_OMP:
+        CmdArgs.push_back("-lomp");
+        break;
+      case Driver::OMPRT_IOMP5:
+        CmdArgs.push_back("-liomp5");
+        break;
+      case Driver::OMPRT_GOMP:
+        CmdArgs.push_back("-lgomp");
+        break;
+      case Driver::OMPRT_Unknown:
+        // Already diagnosed.
+        break;
+      }
+    }
+
     // Support POSIX threads if "-pthreads" or "-pthread" is present.
     if (Args.hasArg(options::OPT_pthreads, options::OPT_pthread))
       CmdArgs.push_back("-lpthreads");