diff --git a/loopy/isl_helpers.py b/loopy/isl_helpers.py
index 49ab3fd68303e18a6bec371fc54db4e63f57346d..5a747d070a47ff89336c22c8237ff03e567d0a8a 100644
--- a/loopy/isl_helpers.py
+++ b/loopy/isl_helpers.py
@@ -203,7 +203,7 @@ def static_extremum_of_pw_aff(pw_aff, constants_only, set_method, what, context)
     if len(pieces) == 1:
         (_, result), = pieces
         if constants_only and not result.is_cst():
-            raise ValueError("a numeric %s was not found for PwAff '%s'"
+            raise StaticValueFindingError("a numeric %s was not found for PwAff '%s'"
                     % (what, pw_aff))
         return result
 
diff --git a/loopy/kernel/__init__.py b/loopy/kernel/__init__.py
index 3f8505631edaff9f27d9e31442cf98f4f0af446a..88a5717642af6d9ebc1bd7770936ae44e8cbf44b 100644
--- a/loopy/kernel/__init__.py
+++ b/loopy/kernel/__init__.py
@@ -41,6 +41,7 @@ from loopy.library.function import (
 
 from loopy.diagnostic import CannotBranchDomainTree, LoopyError
 from loopy.tools import natsorted
+from loopy.diagnostic import StaticValueFindingError
 
 
 # {{{ unique var names
@@ -961,7 +962,7 @@ class LoopKernel(ImmutableRecordWithoutPickling):
                 size = static_max_of_pw_aff(size,
                         constants_only=isinstance(tag, LocalIndexTag),
                         context=self.assumptions)
-            except ValueError:
+            except StaticValueFindingError:
                 pass
 
             tgt_dict[tag.axis] = size