diff --git a/code/constitutive_nonlocal.f90 b/code/constitutive_nonlocal.f90
index 87ff22176..c7c678961 100644
--- a/code/constitutive_nonlocal.f90
+++ b/code/constitutive_nonlocal.f90
@@ -79,7 +79,7 @@ real(pReal), dimension(:,:,:), allocatable ::             constitutive_nonlocal_
                                                           constitutive_nonlocal_forestProjectionScrew, &        ! matrix of forest projections of screw dislocations for each instance
                                                           constitutive_nonlocal_interactionMatrixSlipSlip       ! interaction matrix of the different slip systems for each instance    
 
-logical periodicBC = .false.
+logical :: periodicBC = .false.
 
 
 CONTAINS