Hi ! Please, help me. I need _quickly_ add two _unsigned_ long and test carry flag. For Example: //////////////////////////////////////////////// int AddULong(ulong a, ulong b, ulong *c) { *c = a + b; asm volatile("jc La1"); return 0; // carry == 0 La1: return 1; // carry == 1 } /////////////////////////////////////////////////////////////////////////////////////////////////////////// Compile width gcc-3.2.2 ( in Linux Red Hat 9 ) g++ -DHAVE_CONFIG_H -I. -I. -I.. -Wnon-virtual-dtor -Wno-long-long -Wundef -Wall -pedantic -W -Wpointer-arith -Wmissing-prototypes -Wwrite-strings -ansi -D_XOPEN_SOURCE=500 -D_BSD_SOURCE -Wcast-align -Wconversion -O2 -O0 -g3 -Wall -fno-exceptions -fno-check-new -c -o Mach.o `test -f 'Mach.cpp' || echo './'`Mach.cpp Mach.cpp: warning: label `La1' defined but not used <------ !!!! Mach.cpp: undefined reference to `La1' <------??? //////////////////////////////////////////////////////////////////////////////////////////////////////////// If know how, please mail me. Thanks a lot for your time!! Best regards. Eugene. MailTo ezeml@xxxxxxxxxxx