Commit Graph

18 Commits

Author SHA1 Message Date
Richard Trieu 5b993500ae Improvements to -Wnull-conversion
Split logic to separate checking function
Refine the macro checking
Catch nullptr->bool conversions
Add some explanatory comments

llvm-svn: 219774
2014-10-15 03:42:06 +00:00
David Blaikie bcd4b5521d Don't warn on conversion from NULL to nullptr_t
llvm-svn: 175331
2013-02-16 00:56:22 +00:00
David Blaikie 8cf439f85a PR13165: False positive when initializing member data pointers with NULL.
This now correctly covers, I believe, all the pointer types:
* 'any' pointers (both function and data normal pointers and ObjC object pointers)
* member pointers (both function and data)
* block pointers

llvm-svn: 158931
2012-06-21 18:51:10 +00:00
David Blaikie 9366d2b32d Enable -Wnull-conversion for non-integral target types (eg: double).
llvm-svn: 158744
2012-06-19 21:19:06 +00:00
David Blaikie a5696dff5c Include the correct conversion context locations for condition expressions.
This improves the conversion diagnostics (by correctly pointing to the loop
construct for conversions that may've been caused by the contextual conversion
to bool caused by a condition expression) and also causes the NULL conversion
warnings to be correctly suppressed when crossing a macro boundary in such a
context. (previously, since the conversion context location was incorrect, the
suppression could not be performed)

Reported by Nico Weber as feedback to r156826.

llvm-svn: 156901
2012-05-16 04:20:04 +00:00
David Blaikie 18e9ac7914 Don't warn when NULL is used within a macro but its conversion is outside a macro.
This fixes the included test case & was reported by Nico Weber.

It's a little bit nasty using the difference in the conversion context, but
seems to me like a not unreasonable solution. I did have to fix up the
conversion context for conditional operators (it seems correct to me to include
the context for which we're actually doing the comparison - across all the
nested conditionals, rather than the innermost conditional which might not
actually have the problematic implicit conversion at all) and template default
arguments (this is a bit of a hack, since we don't have the source location of
the '=' anymore, so I just used the start of the parameter - open to
suggestions there)

llvm-svn: 156861
2012-05-15 21:57:38 +00:00
David Blaikie 7555b6a4e5 Improve some of the conversion warnings to fire on conversion to bool.
Moves the bool bail-out down a little in SemaChecking - so now
-Wnull-conversion and -Wliteral-conversion can fire when the target type is
bool.

Also improve the wording/details in the -Wliteral-conversion warning to match
the -Wconstant-conversion.

llvm-svn: 156826
2012-05-15 16:56:36 +00:00
David Blaikie 3890d687e6 Workaround a miscompile in 483.xalancbmk while we figure it out.
llvm-svn: 155938
2012-05-01 20:28:45 +00:00
David Blaikie 7afed5e5bf PR12710 - broken default argument handling for templates.
I broke this in r155838 by not actually instantiating non-dependent default arg
expressions. The motivation for that change was to avoid producing duplicate
conversion warnings for such default args (we produce them once when we parse
the template - there's no need to produce them at each instantiation) but
without actually instantiating the default arg, things break in weird ways.

Technically, I think we could still get the right diagnostic experience without
the bugs if we instantiated the non-dependent args (for non-dependent params
only) immediately, rather than lazily. But I'm not sure if such a refactoring/
change would be desirable so here's the conservative fix for now.

llvm-svn: 155893
2012-05-01 06:05:57 +00:00
David Blaikie f68e809c5e Fix PR12378: provide conversion warnings on default args of function templates
Apparently we weren't checking default arguments when they were instantiated.
This adds the check, fixes the lack of instantiation caching (which seems like
it was mostly implemented but just missed the last step), and avoids
implementing non-dependent default args (for non-dependent parameter types) as
uninstantiated default arguments (so that we don't warn once for every
instantiation when it's not instantiation dependent).

Reviewed by Richard Smith.

llvm-svn: 155838
2012-04-30 18:21:31 +00:00
David Blaikie ae12b18ad8 Suppress macro expansion of NULL in NULL warnings.
For "int i = NULL;" we would produce:

null.cpp:5:11: warning: implicit conversion of NULL constant to integer [-Wconversion]
  int i = NULL;
      ~   ^~~~
null.cpp:1:14: note: expanded from macro 'NULL'
\#define NULL __null
              ^~~~~~

But we really shouldn't trace that macro expansion back into the header, yet we
still want macro back traces for code like this:

\#define FOO NULL
int i = FOO;

or

\#define FOO int i = NULL;
FOO

While providing appropriate tagging at different levels of the expansion, etc.

The included test case exercises these cases & does some basic validation (to
ensure we don't have macro expansion notes where we shouldn't, and do where we
should) - but doesn't go as far as to validate the source location/ranges
used in those notes and warnings.

llvm-svn: 152940
2012-03-16 20:30:12 +00:00
David Blaikie e7fd58006d Provide the specific target type in the -Wnull-conversion warning.
llvm-svn: 152835
2012-03-15 20:48:26 +00:00
David Blaikie ebcbe4b6aa Reapply r152745 (reverted in 152765) now that compiler-rt is fixed.
Original commit message:

Provide -Wnull-conversion separately from -Wconversion.

Like GCC, provide a NULL conversion to non-pointer conversion as a separate
flag, on by default. GCC's flag is "conversion-null" which we provide for
cross compatibility, but in the interests of consistency (with
-Wint-conversion, -Wbool-conversion, etc) the canonical Clang flag is called
-Wnull-conversion.

Patch by Lubos Lunak.
Review feedback by myself, Chandler Carruth, and Chad Rosier.

llvm-svn: 152774
2012-03-15 04:50:32 +00:00
Chad Rosier 2860fbb747 Revert r152745 as it's breaking the internal buildbots.
Abbreviated commit message:
Provide -Wnull-conversion separately from -Wconversion.

llvm-svn: 152765
2012-03-15 01:00:38 +00:00
David Blaikie 1ce8dbb93f Provide -Wnull-conversion separately from -Wconversion.
Like GCC, provide a NULL conversion to non-pointer conversion as a separate
flag, on by default. GCC's flag is "conversion-null" which we provide for
cross compatibility, but in the interests of consistency (with
-Wint-conversion, -Wbool-conversion, etc) the canonical Clang flag is called
-Wnull-conversion.

Patch by Lubos Lunak.
Review feedback by myself, Chandler Carruth, and Chad Rosier.

llvm-svn: 152745
2012-03-14 22:28:22 +00:00
Richard Trieu beaf34531e Add a new warning on NULL pointer constant to integer conversion.
This path was reviewed by Chandler Carruth at http://codereview.appspot.com/4538074/

llvm-svn: 132297
2011-05-29 19:59:02 +00:00
John McCall 1f425648ca Extend the bitfield-truncation warning to initializations.
rdar://problem/8652606

llvm-svn: 118773
2010-11-11 03:21:53 +00:00
John McCall a15eb737e4 Check in this -Wconversion C++ test case that's been sitting on my machine
for awhile.

llvm-svn: 108232
2010-07-13 06:26:23 +00:00