fix link order in PETSc easyblock for SCOTCH >= 7.x

easybuild/easyblocks/p/petsc.py

@@ -237,10 +237,10 @@ def configure_step(self):
                 inc_spec = "-include=[%s]" % ','.join(scotch_inc)
 
                 # For some reason there is a v3 suffix added to libptscotchparmetis
-                # which is the reason for this new code.
-                req_scotch_libs = ['libesmumps.a', 'libptesmumps.a', 'libptscotch.a',
-                                   'libptscotcherr.a', 'libptscotchparmetisv3.a', 'libscotch.a',
-                                   'libscotcherr.a']
+                # which is the reason for this new code;
+                # note: order matters here, don't sort these alphabetically!
+                req_scotch_libs = ['libptesmumps.a', 'libptscotchparmetisv3.a', 'libptscotch.a',
+                                   'libptscotcherr.a', 'libesmumps.a', 'libscotch.a', 'libscotcherr.a']
                 scotch_libs = [os.path.join(scotch, "lib", x) for x in req_scotch_libs]
                 lib_spec = "-lib=[%s]" % ','.join(scotch_libs)
                 self.cfg.update('configopts', ' '.join([withdep + spec for spec in ['=1', inc_spec, lib_spec]]))