diff --git a/src/SdCard/SdSpiCard.h b/src/SdCard/SdSpiCard.h
index d5437ba..2693d20 100644
--- a/src/SdCard/SdSpiCard.h
+++ b/src/SdCard/SdSpiCard.h
@@ -236,7 +236,9 @@ class SdSpiCard {
   uint32_t sectorCount();
 #ifndef DOXYGEN_SHOULD_SKIP_THIS
   // Use sectorCount(). cardSize() will be removed in the future.
-  uint32_t __attribute__((error("use sectorCount()"))) cardSize();
+  uint32_t __attribute__((warning("use sectorCount()"))) cardSize() {
+    return sectorCount();
+  }
 #endif  // DOXYGEN_SHOULD_SKIP_THIS
   /** Set SPI sharing state
    * \param[in] value desired state.