On ARMv7, GCC catches this particular problem and reports trying to copy a string into a space too small; it counts the terminating NULL as part of the char[]. diff -Naur acpica-unix2-20200214.orig/source/components/utilities/utstring.c acpica-unix2-20200214/source/components/utilities/utstring.c --- acpica-unix2-20200214.orig/source/components/utilities/utstring.c 2020-02-14 10:33:55.000000000 -0700 +++ acpica-unix2-20200214/source/components/utilities/utstring.c 2020-02-24 16:52:24.623218044 -0700 @@ -185,7 +185,7 @@ { UINT32 i; BOOLEAN FoundBadChar = FALSE; - UINT32 OriginalName; + char OriginalName[ACPI_NAMESEG_SIZE+1]; ACPI_FUNCTION_NAME (UtRepairName);