diff --git a/cpu/esp_common/Makefile.dep b/cpu/esp_common/Makefile.dep
index 5f01c83b98..b127095471 100644
--- a/cpu/esp_common/Makefile.dep
+++ b/cpu/esp_common/Makefile.dep
@@ -35,6 +35,10 @@ ifneq (,$(filter netdev_default gnrc_netdev_default,$(USEMODULE)))
   endif
 endif
 
+ifneq (,$(filter esp_gdbstub,$(USEMODULE)))
+  USEMODULE += esp_gdb
+endif
+
 # each device has SPI flash memory, but it has to be enabled explicitly
 ifneq (,$(filter esp_spiffs,$(USEMODULE)))
   USEMODULE += spiffs
diff --git a/cpu/esp_common/Makefile.include b/cpu/esp_common/Makefile.include
index 5f01111fef..170266b889 100644
--- a/cpu/esp_common/Makefile.include
+++ b/cpu/esp_common/Makefile.include
@@ -7,10 +7,6 @@ FLASH_MODE ?= dout
 # SPECIAL module dependencies
 # cannot be done in Makefile.dep since Makefile.dep is included too late
 
-ifneq (,$(filter esp_gdbstub,$(USEMODULE)))
-  USEMODULE += esp_gdb
-endif
-
 ifneq (,$(filter log_color,$(USEMODULE)))
   USEMODULE += esp_log_colored
 endif
@@ -55,12 +51,9 @@ ASFLAGS += --longcalls --text-section-literals
 ARFLAGS = rcs
 
 CFLAGS_DBG ?= -ggdb -g3
-CFLAGS_OPT ?= -Os
 
 # override default CFLAGS_OPT in case module esp_gdb is enabled
-ifneq (,$(filter esp_gdb,$(USEMODULE)))
-  CFLAGS_OPT = -Og
-endif
+CFLAGS_OPT ?= $(if $(filter esp_gdb,$(USEMODULE)),-Og,-Os)
 
 CFLAGS += $(CFLAGS_OPT) $(CFLAGS_DBG)