On 10/29/2015 10:49 AM, David Malcolm wrote:
Our documentation describes -Wall as enabling "all the warnings about
constructions that some users consider questionable, and that are easy to avoid
(or modify to prevent the warning), even in conjunction with macros."
I believe that -Wmisleading-indentation meets these criteria, and is
likely to be of benefit to users who may not read release notes; it
warns for indentation that's misleading, but not for indentation
that's merely bad: the former are places where a user will likely
want to fix the code.
The fix is usually easy and obvious: fix the misleadingly-indented
code. If that isn't an option for some reason, pragmas can be used to
turn off the warning for a particular fragment of code:
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wmisleading-indentation"
if (flag)
x = 3;
y = 2;
#pragma GCC diagnostic pop
-Wmisleading-indentation has been tested with a variety of indentation
styles (see gcc/testsuite/c-c++-common/Wmisleading-indentation.c)
and on a variety of real-world projects. For example, in:
https://www.mail-archive.com/gcc-patches@gcc.gnu.org/msg119790.html
Patrick reports:
"Tested by building the linux, git, vim, sqlite and gdb-binutils sources
with -Wmisleading-indentation."
With the tweak earlier in this kit I believe we now have a good
enough signal:noise ratio for this warning to be widely used; hence this
patch adds the warning to -Wall.
Bootstrapped®rtested with x86_64-pc-linux-gnu.
OK for trunk?
gcc/c-family/ChangeLog:
* c.opt (Wmisleading-indentation): Add to -Wall for C and C++.
gcc/ChangeLog:
* doc/invoke.texi (-Wall): Add -Wmisleading-indentation to the
list.
(-Wmisleading-indentation): Update documentation to reflect
being enabled by -Wall in C/C++.
I'm sure we'll get some grief for this :-)
Approved once we're clean in GCC. I'm going to explicitly say that
we'll have to watch for fallout, particularly as we start getting
feedback from Debian & Fedora mass-rebuilds as we approach release time.
If the fallout is too bad, we'll have to reconsider.
I'll pre-approve patches which fix anything caught by this option in GCC
as long as the fix just adjusts whitespace :-)
jeff
