temporary to an lvalue before taking its address. This removes a weird special
case from the AST representation, and allows the constant expression evaluator
to deal with it without (broken) hacks.
llvm-svn: 180866
statement in constexpr functions. Everything which doesn't require variable
mutation is also allowed as an extension in C++11. 'void' becomes a literal
type to support constexpr functions which return 'void'.
llvm-svn: 180022
Add a CXXDefaultInitExpr, analogous to CXXDefaultArgExpr, and use it both in
CXXCtorInitializers and in InitListExprs to represent a default initializer.
There's an additional complication here: because the default initializer can
refer to the initialized object via its 'this' pointer, we need to make sure
that 'this' points to the right thing within the evaluation.
llvm-svn: 179958
For this source:
const int &ref = someStruct.bitfield;
We used to generate this AST:
DeclStmt [...]
`-VarDecl [...] ref 'const int &'
`-MaterializeTemporaryExpr [...] 'const int' lvalue
`-ImplicitCastExpr [...] 'const int' lvalue <NoOp>
`-MemberExpr [...] 'int' lvalue bitfield .bitfield [...]
`-DeclRefExpr [...] 'struct X' lvalue ParmVar [...] 'someStruct' 'struct X'
Notice the lvalue inside the MaterializeTemporaryExpr, which is very
confusing (and caused an assertion to fire in the analyzer - PR15694).
We now generate this:
DeclStmt [...]
`-VarDecl [...] ref 'const int &'
`-MaterializeTemporaryExpr [...] 'const int' lvalue
`-ImplicitCastExpr [...] 'int' <LValueToRValue>
`-MemberExpr [...] 'int' lvalue bitfield .bitfield [...]
`-DeclRefExpr [...] 'struct X' lvalue ParmVar [...] 'someStruct' 'struct X'
Which makes a lot more sense. This allows us to remove code in both
CodeGen and AST that hacked around this special case.
The commit also makes Clang accept this (legal) C++11 code:
int &&ref = std::move(someStruct).bitfield
PR15694 / <rdar://problem/13600396>
llvm-svn: 179250
This change also makes the serialisation store the required semantics,
fixing an issue where PPC128 was always assumed when re-reading a
128-bit value.
llvm-svn: 173139
in case condition type. // rdar://11577384.
Test is conditionalized on x86_64-apple triple as
I am not sure if the INT_MAX/LONG_MAX values in the test
will pass this test for other hosts.
llvm-svn: 172016
with respect to the lower "left-hand-side bitwidth" bits, even when negative);
see OpenCL spec 6.3j. This patch both implements this behaviour in the code
generator and "constant folding" bits of Sema, and also prevents tests
to detect undefinedness in terms of the weaker C99 or C++ specifications
from being applied.
llvm-svn: 171755
GCC has always supported this on PowerPC and 4.8 supports it on all platforms,
so it's a good idea to expose it in clang too. LLVM supports this on all targets.
llvm-svn: 165362
(__builtin_* etc.) so that it isn't possible to take their address.
Specifically, introduce a new type to represent a reference to a builtin
function, and a new cast kind to convert it to a function pointer in the
operand of a call. Fixes PR13195.
llvm-svn: 162962
CheckLValueConstantExpression.
Richard pointed out that using the address of a TLS variable is ok in a
core C++11 constant expression, as long as it isn't part of the eventual
result of constant expression evaluation. Having the check in
CheckLValueConstantExpression accomplishes this.
llvm-svn: 162850
This makes Clang produce an error for code such as:
__thread int x;
int *p = &x;
The lvalue of a thread-local variable cannot be evaluated at compile
time.
llvm-svn: 162835
"castAs<...>->doSomething()". The analyzer was flagging these
as potential null dereferences, which is technically true. The
invariants appear to be that these casts should never fail, so
let's use castAs<> instead and avoid a runtime check.
llvm-svn: 162468
was mistakenly classifying dynamic_casts which might throw as having no side
effects.
Switch it from a visitor to a switch, so it is kept up-to-date as future Expr
nodes are added. Move it from ExprConstant.cpp to Expr.cpp, since it's not
really related to constant expression evaluation.
Since we use HasSideEffect to determine whether to emit an unused global with
internal linkage, this has the effect of suppressing emission of globals in
some cases.
I've left many of the Objective-C cases conservatively assuming that the
expression has side-effects. I'll leave it to someone with better knowledge
of Objective-C than mine to improve them.
llvm-svn: 161388
multidimensional array of class type. Also, preserve zero-initialization when
evaluating an initializer list for an array, in case the initializers refer to
later elements (which have preceding zero-initialization).
llvm-svn: 159904
constexpr function evaluation, and corresponding ASan / valgrind issue in
tests, by storing the corresponding value with the relevant stack frame. This
also prevents re-evaluation of the source of the underlying OpaqueValueExpr,
which makes a major performance difference for certain contrived code (see
testcase update).
llvm-svn: 159189