On 2007-03-11 10:14:39 -0700, Paul Beard wrote:
All I had to do was add "-O0 -Wall -g" to the CFLAGS but for many users that might not be something they're comfortable with. Add to that the additional complication of the instructions reading "-O0 -g- Wall" (the difference a space can make) and the resulting failures and it might prove frustrating.
IMHO, instead of a variant, MacPorts should allow users to specify default compiler options (e.g., CFLAGS) since there are too many possibilities. For instance, though -O0 is better for real debugging purpose, it degrades performance, and in general, -O1 is fine for normal use and still allows a significant core dump in case of crash. Indeed the gcc man page says about the -g option: GCC allows you to use -g with -O. The shortcuts taken by optimized code may occasionally produce surprising results: some variables you declared may not exist at all; flow of control may briefly move where you did not expect it; some statements may not be executed because they compute constant results or their values were already at hand; some statements may execute in different places because they were moved out of loops. Nevertheless it proves possible to debug optimized output. This makes it reasonable to use the optimizer for programs that might have bugs. -- Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/> Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)