C89 allowed a type specifier to be elided with the resulting type being
int, aka implicit int behavior. This feature was subsequently removed
in C99 without a deprecation period, so implementations continued to
support the feature. Now, as with implicit function declarations, is a
good time to reevaluate the need for this support.
This patch allows -Wimplicit-int to issue warnings in C89 mode (off by
default), defaults the warning to an error in C99 through C17, and
disables support for the feature entirely in C2x. It also removes a
warning about missing declaration specifiers that really was just an
implicit int warning in disguise and other minor related cleanups.
-Wfor-loop-analysis warnings for a for-loop with a condition variable. In such
a case, the loop condition variable is modified on each iteration of the loop
by definition.
Original commit message:
Rearrange condition handling so that semantic checks on a condition variable
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.
llvm-svn: 273600
are performed before the other substatements of the construct are parsed,
rather than deferring them until the end. This allows better error recovery
from semantic errors in the condition, improves diagnostic order, and is a
prerequisite for C++17 constexpr if.
llvm-svn: 273548
The motivation is to fix a crash on
struct S {} s;
Foo S::~S() { s.~S(); }
What was happening here was that S::~S() was marked as invalid since its
return type is invalid, and as a consequence CheckFunctionDeclaration() wasn't
called and S::~S() didn't get merged into S's implicit destructor. This way,
the class ended up with two destructors, which confused the overload printer
when it suddenly had to print two possible destructors for `s.~S()`.
In addition to fixing the crash, this change also seems to improve diagnostics
in a few other places, see test changes.
Crash found by SLi's bot.
llvm-svn: 229639
If source code is invalid, error recovery can lead to name lookup in a set containing invalid declaration. The lookup is stopped once found such declaration, but LookupResult object could remain in inconsistent state. Its destructor triggered a check, which caused assert violation.
This patch fixes PR16964 and PR12791.
llvm-svn: 189916
Aaron Ballman