added archer 2.0.0 and package build fixes (#13577)

var/spack/repos/builtin/packages/archer/package.py

@@ -13,15 +13,22 @@ class Archer(CMakePackage):
     homepage = "https://github.com/PRUNERS/ARCHER"
     url      = "https://github.com/PRUNERS/archer/archive/v1.0.0.tar.gz"
 
+    version('2.0.0', sha256='3241cadb0078403368b69166b27f815e12c350486d4ceb3fb33147895b9ebde8')
     version('1.0.0', sha256='df814a475606b83c659932caa30a68bed1c62e713386b375c1b78eb8d60e0d15')
 
     depends_on('cmake@3.4.3:', type='build')
-    depends_on('llvm')
+    depends_on('llvm@:8.0.0')
     depends_on('ninja@1.5:', type='build')
-    depends_on('llvm-openmp-ompt')
+    depends_on('llvm-openmp-ompt@tr6_forwards')
 
     generator = 'Ninja'
 
+    def patch(self):
+        if self.spec.satisfies('^llvm@8.0.0:'):
+            filter_file(r'add_llvm_loadable_module\(LLVMArcher',
+                        'add_llvm_library(LLVMArcher MODULE',
+                        'lib/CMakeLists.txt')
+
     def cmake_args(self):
         return [
             '-DCMAKE_C_COMPILER=clang',