--- a/sopalin/coeftab.h
+++ b/sopalin/coeftab.h
@@ -41,7 +41,7 @@
 /**
  * @brief List of functions to compute the memory gain in low-rank per precision.
  */
-coeftab_fct_memory_t coeftabMemory[4];
+extern coeftab_fct_memory_t coeftabMemory[4];
 
 /**
  * @}