gcc10 LTO - Only specify adhlns assembler options at link time (#15115)

* gcc10 LTO - Only specify adhlns assembler options at link time

* Default adhlns off?

tmk_core/rules.mk

@@ -81,7 +81,6 @@ endif
 #  -f...:        tuning, see GCC manual and avr-libc documentation
 #  -Wall...:     warning level
 #  -Wa,...:      tell GCC to pass this to the assembler.
-#    -adhlns...: create assembler listing
 ifeq ($(strip $(LTO_ENABLE)), yes)
     ifeq ($(PLATFORM),CHIBIOS)
         $(info Enabling LTO on ChibiOS-targeting boards is known to have a high likelihood of failure.)
@@ -117,10 +116,6 @@ endif
 #CFLAGS += -Wundef
 #CFLAGS += -Wunreachable-code
 #CFLAGS += -Wsign-compare
-GCC_VERSION := $(shell gcc --version 2>/dev/null)
-ifeq ($(findstring clang, ${GCC_VERSION}),)
-CFLAGS += -Wa,-adhlns=$(@:%.o=%.lst)
-endif
 CFLAGS += $(CSTANDARD)
 
 # This fixes lots of keyboards linking errors but SHOULDN'T BE A FINAL SOLUTION
@@ -133,7 +128,6 @@ CFLAGS += -fcommon
 #  -f...:        tuning, see GCC manual and avr-libc documentation
 #  -Wall...:     warning level
 #  -Wa,...:      tell GCC to pass this to the assembler.
-#    -adhlns...: create assembler listing
 ifeq ($(strip $(DEBUG_ENABLE)),yes)
   CXXFLAGS += -g$(DEBUG)
 endif
@@ -152,28 +146,10 @@ endif
 #CXXFLAGS += -Wstrict-prototypes
 #CXXFLAGS += -Wunreachable-code
 #CXXFLAGS += -Wsign-compare
-ifeq ($(findstring clang, ${GCC_VERSION}),)
-CXXFLAGS += -Wa,-adhlns=$(@:%.o=%.lst)
-endif
 #CXXFLAGS += $(CSTANDARD)
 
 #---------------- Assembler Options ----------------
-#  -Wa,...:   tell GCC to pass this to the assembler.
-#  -adhlns:   create listing
-#  -gstabs:   have the assembler create line number information; note that
-#             for use in COFF files, additional information about filenames
-#             and function names needs to be present in the assembler source
-#             files -- see avr-libc docs [FIXME: not yet described there]
-#  -listing-cont-lines: Sets the maximum number of continuation lines of hex
-#       dump that will be displayed for a given single line of source input.
 ASFLAGS += $(ADEFS)
-ifeq ($(findstring clang, ${GCC_VERSION}),)
-ifeq ($(strip $(DEBUG_ENABLE)),yes)
-  ASFLAGS += -Wa,-adhlns=$(@:%.o=%.lst),-gstabs,--listing-cont-lines=100
-else
-  ASFLAGS += -Wa,-adhlns=$(@:%.o=%.lst),--listing-cont-lines=100
-endif
-endif
 ifeq ($(VERBOSE_AS_CMD),yes)
 	ASFLAGS += -v
 endif
@@ -230,6 +206,32 @@ LDFLAGS += $(PRINTF_LIB) $(SCANF_LIB) $(MATH_LIB)
 # You can give EXTRALDFLAGS at 'make' command line.
 LDFLAGS += $(EXTRALDFLAGS)
 
+#---------------- Assembler Listings ----------------
+#  -Wa,...:   tell GCC to pass this to the assembler.
+#  -adhlns:   create listing
+#  -gstabs:   have the assembler create line number information; note that
+#             for use in COFF files, additional information about filenames
+#             and function names needs to be present in the assembler source
+#             files -- see avr-libc docs [FIXME: not yet described there]
+#  -listing-cont-lines: Sets the maximum number of continuation lines of hex
+#       dump that will be displayed for a given single line of source input.
+
+ADHLNS_ENABLE ?= no
+ifeq ($(ADHLNS_ENABLE),yes)
+  # Avoid "Options to '-Xassembler' do not match" - only specify assembler options at LTO link time
+  ifeq ($(strip $(LTO_ENABLE)), yes)
+    LDFLAGS += -Wa,-adhlns=$(BUILD_DIR)/$(TARGET).lst
+  else
+    CFLAGS += -Wa,-adhlns=$(@:%.o=%.lst)
+    CXXFLAGS += -Wa,-adhlns=$(@:%.o=%.lst)
+    ifeq ($(strip $(DEBUG_ENABLE)),yes)
+      ASFLAGS = -Wa,-adhlns=$(@:%.o=%.lst),-gstabs,--listing-cont-lines=100
+    else
+      ASFLAGS = -Wa,-adhlns=$(@:%.o=%.lst),--listing-cont-lines=100
+    endif
+  endif
+endif
+
 # Define programs and commands.
 SHELL = sh
 REMOVE = rm -f