diff --git a/Makefile.inc b/Makefile.inc
index 8cec74669d..32952e449d 100644
--- a/Makefile.inc
+++ b/Makefile.inc
@@ -186,7 +186,7 @@ ifeq ($(CONFIG_WARNINGS_ARE_ERRORS),y)
 CFLAGS_common += -Werror
 endif
 CFLAGS_common += -fno-common -ffreestanding -fno-builtin -fomit-frame-pointer
-ifneq ($(GDB_DEBUG),)
+ifneq ($(SOURCE_DEBUG),)
 CFLAGS_common += -O0
 else
 CFLAGS_common += -Os
diff --git a/payloads/libpayload/Makefile.inc b/payloads/libpayload/Makefile.inc
index ea9e404f46..f03968492d 100644
--- a/payloads/libpayload/Makefile.inc
+++ b/payloads/libpayload/Makefile.inc
@@ -61,7 +61,7 @@ CFLAGS += -Wall -Wundef -Wstrict-prototypes -Wmissing-prototypes
 CFLAGS += -Wwrite-strings -Wredundant-decls -Wno-trigraphs
 CFLAGS += -Wstrict-aliasing -Wshadow -Werror
 
-ifneq ($(GDB_DEBUG),)
+ifneq ($(SOURCE_DEBUG),)
 CFLAGS += -O0 -g
 else
 CFLAGS += -Os