They are added by the binutils gold linker.
cpp -DINCLUDE_VARIABLES -P $INCLUDES -DALL_FILES ${srcdir:-.}/gio.symbols | sed -e '/^$/d' -e 's/ G_GNUC.*$//' -e 's/ PRIVATE$//' | sort > expected-abi
rm glibconfig.cpp
-nm -D -g --defined-only .libs/libgio-2.0.so | cut -d ' ' -f 3 | sort > actual-abi
+nm -D -g --defined-only .libs/libgio-2.0.so | cut -d ' ' -f 3 | egrep -v '^(__bss_start|_edata|_end)' | sort > actual-abi
diff -u expected-abi actual-abi && rm expected-abi actual-abi
cpp -P -DINCLUDE_INTERNAL_SYMBOLS -DINCLUDE_VARIABLES -DG_STDIO_NO_WRAP_ON_UNIX -DALL_FILES $INCLUDES "${srcdir:-.}/glib.symbols" | sed -e '/^$/d' -e 's/ G_GNUC.*$//' -e 's/ PRIVATE$//' | sort > expected-abi
rm -f glibconfig.cpp
-nm -D -g --defined-only .libs/libglib-2.0.so | cut -d ' ' -f 3 | sort > actual-abi
+nm -D -g --defined-only .libs/libglib-2.0.so | cut -d ' ' -f 3 | egrep -v '^(__bss_start|_edata|_end)' | sort > actual-abi
diff -u expected-abi actual-abi && rm -f expected-abi actual-abi
cpp -DINCLUDE_VARIABLES -P $INCLUDES -DALL_FILES ${srcdir:-.}/gobject.symbols | sed -e '/^$/d' -e 's/ G_GNUC.*$//' -e 's/ PRIVATE$//' | sort > expected-abi
rm glibconfig.cpp
-nm -D -g --defined-only .libs/libgobject-2.0.so | cut -d ' ' -f 3 | sort > actual-abi
+nm -D -g --defined-only .libs/libgobject-2.0.so | cut -d ' ' -f 3 | egrep -v '^(__bss_start|_edata|_end)' | sort > actual-abi
diff -u expected-abi actual-abi && rm expected-abi actual-abi