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.
Functions without prototypes in C (also known as K&R C functions) were
introduced into C89 as a deprecated feature and C2x is now reclaiming
that syntax space with different semantics. However, Clang's
-Wstrict-prototypes diagnostic is off-by-default (even in pedantic
mode) and does not suffice to warn users about issues in their code.
This patch changes the behavior of -Wstrict-prototypes to only diagnose
declarations and definitions which are not going to change behavior in
C2x mode, and enables the diagnostic in -pedantic mode. The diagnostic
is now specifically about the fact that the feature is deprecated.
It also adds -Wdeprecated-non-prototype, which is grouped under
-Wstrict-prototypes and diagnoses declarations or definitions which
will change behavior in C2x mode. This diagnostic is enabled by default
because the risk is higher for the user to continue to use the
deprecated feature.
Differential Revision: https://reviews.llvm.org/D122895
A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the sixth batch of tests being updated (there are a significant
number of other tests left to be updated).
This diff removes temporary file t2 in fixit.c and updates the test command accordingly.
NFC.
Test plan:
make check-all
Differential revision: https://reviews.llvm.org/D34066
llvm-svn: 305124
This fixes a couple of latent crashes for invalid attributes and also adds a
fixit hint to turn identifiers into string literals if one was expected. It then
proceeds recovery as if the identifier was a literal. Diagnostic locations are
also changed to point at the literal instead of the attribute if the error
concerns the argument. PR17175.
For example:
hidden.c:1:40: error: 'visibility' attribute requires a string
extern int x __attribute__((visibility(hidden)));
^
" "
hidden.c:2:29: error: visibility does not match previous declaration
extern int x __attribute__((visibility("default")));
^
hidden.c:1:29: note: previous attribute is here
extern int x __attribute__((visibility(hidden)));
^
llvm-svn: 190699
start of a statement or the end of a compound-statement, diagnose the comma as
a typo for a semicolon. Patch by Ahmed Bougacha! Additional test cases and
minor refactoring by me.
llvm-svn: 164085
loop and switch statements, by teaching Scope that a function scope never has
a continue/break parent for the purposes of control flow. Remove the hack in
block and lambda expressions which worked around this by pretending that such
expressions were continue/break scopes.
Remove Scope::ControlParent, since it's unused.
In passing, teach default statements to recover properly from a missing ';', and
add a fixit for same to both default and case labels (the latter already
recovered correctly).
llvm-svn: 150776
declaration tickles a bug in the way we handle visibility pragmas.
The improvement to error recovery for template function definitions declared
with the 'typedef' specifier in r145372 is unrelated and not reverted here.
llvm-svn: 145541
declaration at namespace scope is followed by a semicolon and an open-brace
(or in C++, a 'try', ':' or '='), then the error is probably a function
definition with a spurious ';', rather than a mysterious '{'.
llvm-svn: 145372
instead of a semicolon (as sometimes happens during refactorings). When such a
comma is seen at the end of a line, and is followed by something which can't
possibly be a declarator (or even something which might be a plausible typo for
a declarator), suggest that a semicolon was intended.
llvm-svn: 142544
RUN: foo
RUN: bar || true
is equivalent to:
RUN: foo && bar || true
which is equivalent to:
RUN: (foo && bar) || true
This resulted in several of the fixit tests not really testing anything.
llvm-svn: 139132
we don't have enough information to tell them how to use 'strncmp'. Instead, change the
diagnostic to indicate they should use 'strncmp'.
llvm-svn: 100890
- 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