Package: glibc Version: 2.5-3 Debian version: etch Platform: x86_64 GCC version: 4.1.1-15. The following program causes a segmentation violation: $ cat > l.c #include <stdio.h> int main() { double d = 9.9999999999999991e-05; printf("%f\n", d); printf("%e\n", d); printf("%g\n", d); } <CTRL-D> $ gcc l.c $ ./a.out 0.000100 1.000000e-04 Segmentation fault $ That was unexpected :-). - L.