TECHPULP | ELF Binary Optimization for size

July 26, 2008

By: Nick

In Category C/C++ Linux Optimization

The following steps help in reducing the size of a Linux application ELF binary. These operations can be used for application binary as well as shared library.

Use compiler optimization flags

        -Os (optimize for size)
        -O2

While linking, try to use following options. But do not use ‘-s’ option for kernel modules.

# ld -r -s --discard-local --discard-all testApp.o -o testApp
# ld -r -s --discard-local --discard-all testLib1.o testLib2.o -o testLib.so
# ld -r --discard-local --discard-all testMod1.o testMod2.o -o testMod

Strip the binary including unnecessary sections

# strip --remove-section=.note --remove-section=.comment  testApp
# strip --remove-section=.note --remove-section=.comment  testLib.so

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