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.
This patch adds -Wno-strict-prototypes to all of the test cases that
use functions without prototypes, but not as the primary concern of the
test. e.g., attributes testing whether they can/cannot be applied to a
function without a prototype, etc.
This is done in preparation for enabling -Wstrict-prototypes by
default.
This changes clang to match GCC's behavior for __extension__, which temporarily
disables the -pedantic flag. Warnings that are enabled without -pedantic
are not affected. Besides the general goodness of matching GCC's precedent,
my motivation for this is that macros in the arm_neon.h header need to use
__extension__ to avoid pedantic complaints about their use of statement
expressions, yet we still want to warn about incompatible pointer arguments
for those macros.
llvm-svn: 141804
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
start of the declspec. The fixit still goes there, and we underline
the declspec. This helps when the start of the declspec came from a
macro that expanded from a system header. For example, we now produce:
t.c:2:8: warning: type specifier missing, defaults to 'int' [-Wimplicit-int]
static x;
~~~~~~ ^
llvm-svn: 69777
in C89 mode. This makes it enabled by default instead of only enabled with
-pedantic. Clang defaults to c99 mode, so people will see this more often
than with GCC, but they can always use -std=c89 if they really want c89.
llvm-svn: 65647
Aaron Ballman