Strengthen -Wint-conversion to default to an error

Clang has traditionally allowed C programs to implicitly convert
integers to pointers and pointers to integers, despite it not being
valid to do so

Strengthen -Wint-conversion to default to an error

Clang has traditionally allowed C programs to implicitly convert
integers to pointers and pointers to integers, despite it not being
valid to do so except under special circumstances (like converting the
integer 0, which is the null pointer constant, to a pointer). In C89,
this would result in undefined behavior per 3.3.4, and in C99 this rule
was strengthened to be a constraint violation instead. Constraint
violations are most often handled as an error.

This patch changes the warning to default to an error in all C modes
(it is already an error in C++). This gives us better security posture
by calling out potential programmer mistakes in code but still allows
users who need this behavior to use -Wno-error=int-conversion to retain
the warning behavior, or -Wno-int-conversion to silence the diagnostic
entirely.

Differential Revision: https://reviews.llvm.org/D129881

show more ...

Add prototypes to functions which need them; NFC

Recommit: Compress formatting of array type names (int [4] -> int[4])

Based on post-commit review discussion on
2bd84938470bf2e337801faafb8a67710f46429d with Richard Smith.

Other uses of forcing Ha

Recommit: Compress formatting of array type names (int [4] -> int[4])

Based on post-commit review discussion on
2bd84938470bf2e337801faafb8a67710f46429d with Richard Smith.

Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).

This was originally committed in 277623f4d5a672d707390e2c3eaf30a9eb4b075c

Reverted in f9ad1d1c775a8e264bebc15d75e0c6e5c20eefc7 due to breakages
outside of clang - lldb seems to have some strange/strong dependence on
"char [N]" versus "char[N]" when printing strings (not due to that name
appearing in DWARF, but probably due to using clang to stringify type
names) that'll need to be addressed, plus a few other odds and ends in
other subprojects (clang-tools-extra, compiler-rt, etc).

show more ...

Revert "Compress formatting of array type names (int [4] -> int[4])"

Looks like lldb has some issues with this - somehow it causes lldb to
treat a "char[N]" type as an array of chars (prints them ou

Revert "Compress formatting of array type names (int [4] -> int[4])"

Looks like lldb has some issues with this - somehow it causes lldb to
treat a "char[N]" type as an array of chars (prints them out
individually) but a "char [N]" is printed as a string. (even though the
DWARF doesn't have this string in it - it's something to do with the
string lldb generates for itself using clang)

This reverts commit 277623f4d5a672d707390e2c3eaf30a9eb4b075c.

show more ...

Compress formatting of array type names (int [4] -> int[4])

Based on post-commit review discussion on
2bd84938470bf2e337801faafb8a67710f46429d with Richard Smith.

Other uses of forcing HasEmptyPlac

Compress formatting of array type names (int [4] -> int[4])

Based on post-commit review discussion on
2bd84938470bf2e337801faafb8a67710f46429d with Richard Smith.

Other uses of forcing HasEmptyPlaceHolder to false seem OK to me -
they're all around pointer/reference types where the pointer/reference
token will appear at the rightmost side of the left side of the type
name, so they make nested types (eg: the "int" in "int *") behave as
though there is a non-empty placeholder (because the "*" is essentially
the placeholder as far as the "int" is concerned).

show more ...

[Sema] Put existing warning under -Wexcess-initializers

I have a follow-on patch that uses an alternative wording for
ext_excess_initializers in some cases. This patch puts it and
a couple of relat

[Sema] Put existing warning under -Wexcess-initializers

I have a follow-on patch that uses an alternative wording for
ext_excess_initializers in some cases. This patch puts it and
a couple of related warnings under their own -W option in order
to avoid a regression in Misc/warning-flags.c.

Differential Revision: https://reviews.llvm.org/D79244

show more ...

Switch C compilations to C11 by default.

This is long-since overdue, and matches GCC 5.0. This should also be
backwards-compatible, because we already supported all of C11 as an extension
in C99 mod

Switch C compilations to C11 by default.

This is long-since overdue, and matches GCC 5.0. This should also be
backwards-compatible, because we already supported all of C11 as an extension
in C99 mode.

llvm-svn: 220244

show more ...

Improved location for non-constant initializers diagnostics.

llvm-svn: 209466

Recognition of empty structures and unions is moved to semantic stage

Differential Revision: http://llvm-reviews.chandlerc.com/D586

llvm-svn: 183609

Fix assert if __extension__ or _Generic is used when initializing a char array from a string literal.

llvm-svn: 181174

PR13881: Add -Wzero-length-array for zero length array extension, and move it into -Wgnu.

llvm-svn: 164272

clang/test: [PR8833] Introduce the feature "LP64" to suppress LLP64-incompatible tests.

I think some of them could be rewritten to fit also LLP64.

llvm-svn: 163699

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 tar

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

show more ...

Enable warn_impcast_literal_float_to_integer by default.

This diagnostic seems to be production ready, it's just an oversight that it
wasn't turned on by default.

The test changes are a bit of a mi

Enable warn_impcast_literal_float_to_integer by default.

This diagnostic seems to be production ready, it's just an oversight that it
wasn't turned on by default.

The test changes are a bit of a mixed bag. Some tests that seemed like they
clearly didn't need to use this behavior have been modified not to use it.
Others that I couldn't be sure about, I added the necessary expected-warnings
to.

It's possible the diagnostic message could be improved to make it clearer that
this warning can be suppressed by using a value that won't lose precision when
converted to the target type (but can still be a floating point literal, such
as "bool b = 1.0;").

llvm-svn: 154068

show more ...

Don't warn about anonymous struct/union in C11.

Also, in C, call this a C11 extension rather than a GNU extension.

llvm-svn: 149695

The value of a const weak variable is not an integer constant.

llvm-svn: 147575

Change the diagnostics which said 'accepted as an extension' to instead say
'is an extension'. The former is inappropriate and confusing when building with
-Werror/-pedantic-errors.

llvm-svn: 147357

Add list initialization for complex numbers in C. Essentially, this allows "_Complex float x = {1.0f, 2.0f};". See changes to docs/LanguageExtensions.html for a longer description.

<rdar://problem

Add list initialization for complex numbers in C. Essentially, this allows "_Complex float x = {1.0f, 2.0f};". See changes to docs/LanguageExtensions.html for a longer description.

<rdar://problem/9397672>.

llvm-svn: 140090

show more ...

Implement the GNU C extension which permits the initialization of an
array from a constant array compound literal. Fixes PR9261.

llvm-svn: 126230

PR3344: Downgrade "too many braces around scalar initializer" to a warning.

llvm-svn: 111067

Reword the empty struct/union warning in C to note that such structs and unions have size 0 in C, size 1 in C++. Put this warning under -Wc++-compat.

llvm-svn: 109748

Improve diagnostics like "initializing <type> from an expression of
type..." with "initializing <type> with an expression of type...",
which reads better. Thanks to John for the improved wording.

ll

Improve diagnostics like "initializing <type> from an expression of
type..." with "initializing <type> with an expression of type...",
which reads better. Thanks to John for the improved wording.

llvm-svn: 100873

show more ...

Improve diagnostics when we fail to convert from a source type to a
destination type for initialization, assignment, parameter-passing,
etc. The main issue fixed here is that we used rather confusing

Improve diagnostics when we fail to convert from a source type to a
destination type for initialization, assignment, parameter-passing,
etc. The main issue fixed here is that we used rather confusing
wording for diagnostics such as

t.c:2:9: warning: initializing 'char const [2]' discards qualifiers,
expected 'char *' [-pedantic]
char *name = __func__;
^ ~~~~~~~~

We're not initializing a 'char const [2]', we're initializing a 'char
*' with an expression of type 'char const [2]'. Similar problems
existed for other diagnostics in this area, so I've normalized them all
with more precise descriptive text to say what we're
initializing/converting/assigning/etc. from and to. The warning for
the code above is now:

t.c:2:9: warning: initializing 'char *' from an expression of type
'char const [2]' discards qualifiers [-pedantic]
char *name = __func__;
^ ~~~~~~~~

Fixes <rdar://problem/7447179>.

llvm-svn: 100832

show more ...

Initialization improvements: addition of string initialization and a few
small bug fixes in SemaInit, switch over SemaDecl to use it more often, and
change a bunch of diagnostics which are different

Initialization improvements: addition of string initialization and a few
small bug fixes in SemaInit, switch over SemaDecl to use it more often, and
change a bunch of diagnostics which are different with the new initialization
code.

llvm-svn: 91767

show more ...

Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead o

Update tests to use %clang_cc1 instead of 'clang-cc' or 'clang -cc1'.
- 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

show more ...