Package: src:gcms Version: 1.1-2 Tags: patch gcc -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -Wl,-Bsymbolic-functions -Wl,-z,relro -lm -o gsmc autotune.o calc.o dataconv.o draw.o main.o print.o widget.o -lgtk-x11-2.0 -lgdk-x11-2.0 -lpangocairo-1.0 -latk-1.0 -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lpangoft2-1.0 -lpango-1.0 -lgobject-2.0 -lglib-2.0 -lfontconfig -lfreetype /usr/bin/ld: autotune.o: undefined reference to symbol 'sqrtf@@GLIBC_2.2.5' /usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/libm.so: error adding symbols: DSO missing from command line collect2: error: ld returned 1 exit status Makefile:393: recipe for target 'gsmc' failed make[1]: *** [gsmc] Error 1
patch at http://launchpadlibrarian.net/214414209/gsmc_1.1-2_1.1-2ubuntu1.diff.gz looks like your add-lm-to-ldflags.patch is wrong.
