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

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[OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)

This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be p

[OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)

This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115

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Use functions with prototypes when appropriate; NFC

A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a protot

Use functions with prototypes when appropriate; NFC

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 tenth batch of tests being updated (there are a
significant number of other tests left to be updated).

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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).

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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.

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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).

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[test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences

For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and

[test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences

For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and Mach-O. Since default clang -cc1 for ELF is similar
to -fpic ("PIC Level" is not set), this nuance causes unneeded binary format differences.

To make emitted IR similar, ELF -cc1 -fpic will default to -fno-semantic-interposition,
which sets dso_local for default visibility external linkage definitions.

To make this flip smooth and enable future (dso_local as definition default),
this patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `.

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[Sema] Adds the pointer-to-int-cast diagnostic

Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
ha

[Sema] Adds the pointer-to-int-cast diagnostic

Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.

Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.

Fixes PR8718: No warning on casting between pointer and non-pointer-sized int

Differential Revision: https://reviews.llvm.org/D72231

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Revert "[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition"

This reverts commit 789a46f2d742e11edaade28cb59a0f4d2a1d770e.

Accidentally committed.

[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition

Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to sp

[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition

Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865

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Fix reliance on lax vector conversions in tests for x86 intrinsics.

llvm-svn: 372062

[CodeGen] Always use string computed in Sema for PredefinedExpr

We can't use any other string, anyway, because its type wouldn't
match the type of the PredefinedExpr.

With this change, we don't com

[CodeGen] Always use string computed in Sema for PredefinedExpr

We can't use any other string, anyway, because its type wouldn't
match the type of the PredefinedExpr.

With this change, we don't compute a "nice" name for the __func__ global
when it's used in the initializer for a constant. This doesn't seem like
a great loss, and I'm not sure how to fix it without either storing more
information in the AST, or somehow threading through the information
from ExprConstant.cpp.

This could break some situations involving BlockDecl; currently,
CodeGenFunction::EmitPredefinedLValue has some logic to intentionally
emit a string different from what Sema computed. This code skips that
logic... but that logic can't work correctly in general anyway. (For
example, sizeof(__func__) returns the wrong result.) Hopefully this
doesn't affect practical code.

Fixes https://bugs.llvm.org/show_bug.cgi?id=40313 .

Differential Revision: https://reviews.llvm.org/D56821

llvm-svn: 351766

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Revert r332847; it caused us to miscompile certain forms of reference initialization.

llvm-svn: 332886

[CodeGen] Recognize more cases of zero initialization

If a variable has an initializer, codegen tries to build its value. If
the variable is large in size, building its value requires substantial
re

[CodeGen] Recognize more cases of zero initialization

If a variable has an initializer, codegen tries to build its value. If
the variable is large in size, building its value requires substantial
resources. It causes strange behavior from user viewpoint: compilation
of huge zero initialized arrays like:

char data_1[2147483648u] = { 0 };

consumes enormous amount of time and memory.

With this change codegen tries to determine if variable initializer is
equivalent to zero initializer. In this case variable value is not
constructed.

This change fixes PR18978.

Differential Revision: https://reviews.llvm.org/D46241

llvm-svn: 332847

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[CodeGen] Use pointer-sized integers for ptrtoint sources

Given something like:
void *v = (void *)100;

We need to synthesize a ptrtoint operation from 100. During constant
emission, we choose i64

[CodeGen] Use pointer-sized integers for ptrtoint sources

Given something like:
void *v = (void *)100;

We need to synthesize a ptrtoint operation from 100. During constant
emission, we choose i64 as the type for our constant because it
guaranteed not to drop any bits from our CharUnits representation of the
value. However, this is suboptimal for 32-bit targets: LLVM passes like
GlobalOpt will get confused by these sorts of casts resulting in
pessimization.

Instead, make sure the ptrtoint operand has a pointer-sized integer
type.

llvm-svn: 273020

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Test case updates for explicit type parameter to the gep operator

llvm-svn: 232187

CodeGen: ConstStructBuilder must verify packed constraints after padding

This reverts commit r220169 which reverted r220153. However, it also
contains additional changes:
- We may need to add paddi

CodeGen: ConstStructBuilder must verify packed constraints after padding

This reverts commit r220169 which reverted r220153. However, it also
contains additional changes:
- We may need to add padding *after* we've packed the struct. This
occurs when the aligned next field offset is greater than the new
field's offset. When this occurs, we make the struct packed.
*However*, once packed the next field offset might be less than the
new feild's offset. It is in this case that we might further pad the
struct.
- We would pad structs which were perfectly sized! This behavior is
immensely old. This behavior came from blindly subtracting
NextFieldOffsetInChars from RecordSize. This doesn't take into
account the fact that the struct might have a greater overall
alignment than the last field.

llvm-svn: 220175

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Revert r220153: "CodeGen: ConstStructBuilder must verify packed constraints after padding"

This commit caused two tests in LNT to regress. I'm able to reproduce on
any platform and will send reprodu

Revert r220153: "CodeGen: ConstStructBuilder must verify packed constraints after padding"

This commit caused two tests in LNT to regress. I'm able to reproduce on
any platform and will send reproduction steps to the original commit
log. This should restore the LNT bots that have been failing.

llvm-svn: 220169

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CodeGen: ConstStructBuilder must verify packed constraints after padding

Before, ConstStructBuilder::AppendBytes would check packed constraints
prior to padding being added before the field's offset

CodeGen: ConstStructBuilder must verify packed constraints after padding

Before, ConstStructBuilder::AppendBytes would check packed constraints
prior to padding being added before the field's offset. However, adding
this padding might force our struct to be packed. Because we wouldn't
check *after* adding padding, ConstStructBuilder would be in an
inconsistent state leading to a crash.

This fixes PR21300.

llvm-svn: 220153

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Add missing expected-warning.

llvm-svn: 185644

Fix InitListExpr::isStringLiteralInit so it handles various edge cases correctly. PR13643.

llvm-svn: 162226

Add support for bitcasts to vector type in Evaluate.

llvm-svn: 147137

fix an unintended behavior change in the type system rewrite, which caused us to compile
stuff like this:

typedef struct {
int x, y, z;
} foo_t;

foo_t g;

into:
%"struct.<anonymous>" = type { i32

fix an unintended behavior change in the type system rewrite, which caused us to compile
stuff like this:

typedef struct {
int x, y, z;
} foo_t;

foo_t g;

into:
%"struct.<anonymous>" = type { i32, i32, i32 }
we now get:
%struct.foo_t = type { i32, i32, i32 }

This doesn't change the behavior of the compiler, but makes the IR much easier to read.

llvm-svn: 134969

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clang side to match the LLVM IR type system rewrite patch.

llvm-svn: 134831

Update to match mainline ConstantStruct::get API change. Also, use
ConvertType on InitListExprs as they are being converted. This is
needed for a forthcoming patch, and improves the IR generated a

Update to match mainline ConstantStruct::get API change. Also, use
ConvertType on InitListExprs as they are being converted. This is
needed for a forthcoming patch, and improves the IR generated anyway
(see additional type names in testcases).

This patch also converts a bunch of std::vector's in CGObjCMac to use
C arrays. There are a ton more that should be converted as well.

llvm-svn: 133413

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