AVR - C++ and lib generation no functionnal Topic is solved

[Philippe Leduc]

Hello,

Compiler rules for AVR seems to miss some informations for C++ and ar call is not working.

ChibiOS 21.11.2
Compiler: avr-gcc 5.4.0
Platform and board: atmeg328p - arduino nano - demo RT

C++ compilation does not work if it includes AVR hardware. For instance:

Code: Select all

main.cpp:20:22: error: ‘IOPORT4’ was not declared in this scope

Moreover, the make lib is not working as expected:

Code: Select all

avr-ar: two different operation options specified

This report could be split in two but since it is related to only one file I reported once. Tell me if this is a problem.

Following is a patch that resolve the bugs in AVR GCC rules.mk file. For C++ flags I mostly copy/paste C flags and only update the required standard.

Code: Select all

--- vanilla/ChibiOS_21.11.2/os/common/ports/AVR/compilers/GCC/rules.mk  2017-09-16 16:02:09.000000000 +0200
+++ ChibiOS_21.11.2/os/common/ports/AVR/compilers/GCC/rules.mk  2022-08-25 20:03:07.339113729 +0200
@@ -81,6 +81,12 @@
 CFLAGS  += -std=gnu11 -mrelax -fdata-sections -ffunction-sections
 CFLAGS  += -Wundef -MMD -MP #-MF
 
+CPPFLAGS = $(MCFLAGS) -I. -gdwarf-2 $(CDEFS) $(OPT) -funsigned-char
+CFLAGS  += -funsigned-bitfields -fpack-struct -fshort-enums $(CWARN)
+CFLAGS  += -Wa,-adhlns=$(LSTDIR)/$(notdir $(<:.c=.lst)) $(DEFS)
+CFLAGS  += -std=gnu++11 -mrelax -fdata-sections -ffunction-sections
+CFLAGS  += -Wundef -MMD -MP #-MF
+
 #---------------- Assembler Options ----------------
 #  -Wa,...:   tell GCC to pass this to the assembler.
 #  -adhlns:   create listing
@@ -264,7 +270,7 @@
 lib: $(OBJS) $(BUILDDIR)/lib$(PROJECT).a
 
 $(BUILDDIR)/lib$(PROJECT).a: $(OBJS)
-       @$(AR) -r $@ $^
+       @$(AR) $@ $^
        @echo
        @echo Done

[tfAteba]

Hi Philippe,

Thanks for you feed back and the patch.

Sorry I'm not use to look at general bug reports that why I did not see your message. A usually look to the AVR support.

I will make some test with you patch, and your set up.

I never test c++ in Arduino side, so it will be interesting to do that.

You will be notify as soon as I will give a try

[tfAteba]

Hi Philippe,

Compiler rules for AVR seems to miss some informations for C++ and ar call is not working.

Yes it was just CPP flags that was missing. Now it is ok in ChibiOS/trunk, I have just commited a fix for that.

Note that there is a problem with you patch (you are mixing C and CPP flags):

+CFLAGS += -funsigned-bitfields -fpack-struct -fshort-enums $(CWARN)
+CFLAGS += -Wa,-adhlns=$(LSTDIR)/$(notdir $(<:.c=.lst)) $(DEFS)
+CFLAGS += -std=gnu++11 -mrelax -fdata-sections -ffunction-sections
+CFLAGS += -Wundef -MMD -MP #-MF

Those must be CPP flags.

I still need to look at the make lib.

But the C++ compilation is now using the AVR Hardware.

I have create a C++ demo under demos/AVR/RT-ARDUINO-UNO-G++ in the trunk.

[tfAteba]

Hi all,

I still need to look at the make lib.

Thanks for the patch in the library generation side.

So every thing have been fixed and committed in trunk.