but when the good old days memories are needed, then you can still bring that back...
go set the verbose compile in the preferences
compile and then look at one of the last very long line at the end that starts with
Linking everything together...
"/Applications/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-gcc" -Os -flto -fuse-linker-plugin [color=red]-Wl,--gc-sections[/color] -mmcu=atmega328p -o "[color=blue]/var/folders/xk/mwl4yt3j5rsgdmgmgjlqsk7w0000gn/T/arduino_build_432201[/color]/test.ino.elf" "/var/folders/xk/mwl4yt3j5rsgdmgmgjlqsk7w0000gn/T/arduino_build_432201/sketch/test.ino.cpp.o" ......
copy that whole line below "Linking everything together" into you favorite text editor and change the red part to add the orange part with no space [color=red]-Wl,--gc-sections[/color][color=orange],-Map=myfile.map[/color]
and copy the whole thing again with the added [color=orange],-Map=myfile.map[/color]
open terminal
cd to whatever your blue path above is for your project (the temp directory for building)
paste the command line
it will link again and generate a myfile.map in the current directory from which you can probably get the information you want.