-Wno-unused-varialbe flag has no effect

[LMHmedchem]

Hello,

I have an application that I just brought into eclipse. I have previously just built this application from the command line. I am looking to suppress some warnings in the short term but find this is not entirely working.

In the make file,

# add linux version flag to CFLAGS
ifeq "$(CC++)" "g++"
   CFLAGS =  $(OPTIMIZE)  -DLINVGCC4 -DDATESTR=$(DATESTR2) $(DEFRELS) -I src -Wall
endif

# supress some c++ warnings
#CFLAGS := $(CFLAGS) -Wno-sign-compare -Wno-unused-variable

The -Wno-sign-compare flag works and I don't get these warnings. I am still getting the unused-variable warnings, so I don't understand what I am missing here.

This is g++ (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39), CentOS 7.7, built in Eclipse 20191212-1212, using a gnu makefile.

Thanks,

LMHmedchem

[salem_c]

Was it the switch from using = to using := in your assignments?

Makefiles can be very picky things when it comes to evaluating variables, and the two forms mean two very different things.

[LMHmedchem]

Was it the switch from using = to using := in your assignments?

Makefiles can be very picky things when it comes to evaluating variables, and the two forms mean two very different things.

I always use := when adding to a variable that has already been assigned.

I would do,

# set for most warnings
CFLAGS = -Wall
# add to CFLAGS to supress some warnings in all
CFLAGS := $(CFLAGS) -Wno-sign-compare

if I wanted to add something to CFLAGS after it has been defined and assigned some value.

My understanding is that this will simply expand $(CFLAGS) before assigning it back along with the additions. If this is not the correct method, I would appreciate some feedback on that.

It does seem to be working now. When I added the no-sign-compare flag, it seemed to not do anything until I had rebuilt several times.

LMHmedchem