1 files changed, 38 insertions, 25 deletions

diff --git a/var/spack/repos/builtin/packages/intel-oneapi-mkl/package.py b/var/spack/repos/builtin/packages/intel-oneapi-mkl/package.py
index 2f47cf3fb7..bbd0e2b350 100644
--- a/var/spack/repos/builtin/packages/intel-oneapi-mkl/package.py
+++ b/var/spack/repos/builtin/packages/intel-oneapi-mkl/package.py
@@ -74,41 +74,54 @@ class IntelOneapiMkl(IntelOneApiLibraryPackage):
     def component_dir(self):
         return 'mkl'
 
-    def xlp64_lib(self, lib):
-        return lib + ('_ilp64'
-                      if '+ilp64' in self.spec
-                      else '_lp64')
-
     @property
     def headers(self):
-        include_path = join_path(self.component_path, 'include')
-        return find_headers('*', include_path)
-
-    # provide cluster libraries if +cluster variant is used or
-    # the scalapack virtual package was requested
-    def cluster(self):
-        return '+cluster' in self.spec
+        return find_headers('*', self.component_prefix.include)
 
     @property
     def libs(self):
         shared = '+shared' in self.spec
-        mkl_libs = []
-        if self.cluster():
-            mkl_libs += [self.xlp64_lib('libmkl_scalapack'),
-                         'libmkl_cdft_core']
-        mkl_libs += [self.xlp64_lib('libmkl_intel'),
-                     'libmkl_sequential',
-                     'libmkl_core']
-        if self.cluster():
-            mkl_libs += [self.xlp64_lib('libmkl_blacs_intelmpi')]
-        libs = find_libraries(mkl_libs,
-                              join_path(self.component_path, 'lib', 'intel64'),
-                              shared=shared)
+
+        libs = self._find_mkl_libs(shared)
+
         system_libs = find_system_libraries(['libpthread', 'libm', 'libdl'])
         if shared:
             return libs + system_libs
         else:
             return IntelOneApiStaticLibraryList(libs, system_libs)
 
+    def setup_run_environment(self, env):
+        super(IntelOneapiMkl, self).setup_run_environment(env)
+
+        # Support RPATH injection to the library directories when the '-mkl' or '-qmkl'
+        # flag of the Intel compilers are used outside the Spack build environment. We
+        # should not try to take care of other compilers because the users have to
+        # provide the linker flags anyway and are expected to take care of the RPATHs
+        # flags too. We prefer the __INTEL_POST_CFLAGS/__INTEL_POST_FFLAGS flags over
+        # the PRE ones so that any other RPATHs provided by the users on the command
+        # line come before and take precedence over the ones we inject here.
+        for d in self._find_mkl_libs('+shared' in self.spec).directories:
+            flag = '-Wl,-rpath,{0}'.format(d)
+            env.append_path('__INTEL_POST_CFLAGS', flag, separator=' ')
+            env.append_path('__INTEL_POST_FFLAGS', flag, separator=' ')
+
     def setup_dependent_build_environment(self, env, dependent_spec):
-        env.set('MKLROOT', self.component_path)
+        env.set('MKLROOT', self.component_prefix)
+
+    def _find_mkl_libs(self, shared):
+        libs = []
+
+        if '+cluster' in self.spec:
+            libs.extend([self._xlp64_lib('libmkl_scalapack'), 'libmkl_cdft_core'])
+
+        libs.extend([self._xlp64_lib('libmkl_intel'),
+                     'libmkl_sequential', 'libmkl_core'])
+
+        if '+cluster' in self.spec:
+            libs.append(self._xlp64_lib('libmkl_blacs_intelmpi'))
+
+        return find_libraries(
+            libs, self.component_prefix.lib.intel64, shared=shared)
+
+    def _xlp64_lib(self, lib):
+        return lib + ('_ilp64' if '+ilp64' in self.spec else '_lp64')