aocc 3.1.0: fix version detection for v3.1.0 (#25084)

lib/spack/spack/compilers/aocc.py

@@ -98,15 +98,12 @@ def fc_pic_flag(self):
     @classmethod
     @llnl.util.lang.memoized
     def extract_version_from_output(cls, output):
-        loc_ver = 'unknown'
-
         match = re.search(
-            r'AMD clang version ([^ )]+)',
+            r'AOCC_(\d+)[._](\d+)[._](\d+)',
             output
         )
         if match:
-            loc_ver = output.split('AOCC_')[1].split('-')[0]
-        return loc_ver
+            return '.'.join(match.groups())
 
     @classmethod
     def fc_version(cls, fortran_compiler):

lib/spack/spack/test/compilers/detection.py

@@ -345,6 +345,11 @@ def _module(cmd, *args):
 
 @pytest.mark.parametrize('version_str,expected_version', [
     # This applies to C,C++ and FORTRAN compiler
+    ('AMD clang version 12.0.0 (CLANG: AOCC_3_1_0-Build#126 2021_06_07)'
+     '(based on LLVM Mirror.Version.12.0.0)\n'
+     'Target: x86_64-unknown-linux-gnu\n'
+     'Thread model: posix\n', '3.1.0'
+     ),
     ('AMD clang version 12.0.0 (CLANG: AOCC_3.0.0-Build#78 2020_12_10)'
      '(based on LLVM Mirror.Version.12.0.0)\n'
      'Target: x86_64-unknown-linux-gnu\n'