diff --git a/cmake_targets/macros.cmake b/cmake_targets/macros.cmake
index 169ef600ce..c19eb285ef 100644
--- a/cmake_targets/macros.cmake
+++ b/cmake_targets/macros.cmake
@@ -83,7 +83,7 @@ function(run_asn1c ASN1C_GRAMMAR ASN1C_PREFIX)
   get_filename_component(GRAMMAR_FILE ${ASN1C_GRAMMAR} NAME)
   set(LOGFILE "${CMAKE_CURRENT_BINARY_DIR}/${GRAMMAR_FILE}.log")
   add_custom_command(OUTPUT ${ASN1C_OUTPUT}
-    COMMAND ASN1C_PREFIX=${ASN1C_PREFIX} ${ASN1C_EXEC} ${ASN1C_OPTIONS} -D ${CMAKE_CURRENT_BINARY_DIR} ${ASN1C_GRAMMAR} > ${LOGFILE} 2>&1 || cat ${LOGFILE}
+    COMMAND ASN1C_PREFIX=${ASN1C_PREFIX} ${ASN1C_EXEC} ${ASN1C_OPTIONS} -D ${CMAKE_CURRENT_BINARY_DIR} ${ASN1C_GRAMMAR} > ${LOGFILE} 2>&1 || ( cat ${LOGFILE} && false )
     DEPENDS ${ASN1C_GRAMMAR}
     COMMENT "Generating ${ASN1C_COMMENT} from ${GRAMMAR_FILE}"
   )