On Tue, Aug 17, 2004 at 06:25:30AM -0500, Aaron W. LaFramboise wrote:
Daryle Walker wrote:
I don't understand what problem this change is going to solve. If a compiler has a strict C++-1998 mode, then supporting "(unsigned) long long" anyway is sort-of a disfeature. Maybe we should just have the headers assume that the double-long types are absent. (The changes don't affect compilers that don't have the double-long types at all, right?)
The -std=c++98 option (also called -ansi) causes gcc to become standards compliant. Without it, gcc implements a nonstandard "GNU" dialect of C++. People who desire standards conformance and better compile-time checking often use this option. For many C++ projects, all files are compiled with it along with the more familiar -Wall.
As a side effect, it causes errors to be generated when the long long typename is used unadorned.
This isn't strictly true. "long long" will be accepted without any diagnostic, even with "-ansi -Wall", it is "-pedantic" that causes it to be rejected. I tested this on Linux and FreeBSD, with 2.95 and 3.[0345], and the doc links you gave confirm it: The -ansi option does not cause non-ISO programs to be rejected gratuitously. For that, -pedantic is required in addition to -ansi. See Warning Options.
(I've heard this might be changed in the future, as long long might not actually conflict with the standard.) All of the support is still there, including from the standard library. You can still use long long provided you add __extension__, as documented in the manual.
To further clarify, -std=c++98 does not disable long long, and in general, does not disable extensions. It just means you need to use a special syntax when you use the long long type name.
To further clarify, it's -pedantic that means you need __extension__, with or without -std=c++98 / -ansi
So, to answer your question, this patch makes Boost compile for people who use the very common practice of compiling with -std=c++98 (or -pedantic).
This should read "... practice of compiling with -pedantic." jon -- "Any sufficiently advanced bug is indistinguishable from a feature" - Rich Kulawiec