clang has generated correct IR for char/short decrement since r126816,
but we didn't have any test coverage for decrement.
Patch by Andrew Rogers.
llvm-svn: 291805
__builtin_frame_address requires its argument to be a constant
expression which already implies that it cannot have undefined behavior.
However, we used EmitScalarExpr to emit the argument causing UBSan to
try to check for overflow.
Instead, use the constant expression emission system.
This fixes PR24256.
llvm-svn: 243206
Summary:
Make sure signed overflow in "x--" is checked with
llvm.ssub.with.overflow intrinsic and is reported as:
"-2147483648 - 1 cannot be represented in type 'int'"
instead of:
"-2147483648 + -1 cannot be represented in type 'int'"
, like we do for unsigned overflow.
Test Plan: clang + compiler-rt regression test suite
Reviewers: rsmith
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8236
llvm-svn: 235568
checks to enable. Remove frontend support for -fcatch-undefined-behavior,
-faddress-sanitizer and -fthread-sanitizer now that they don't do anything.
llvm-svn: 167413
by this mode, and also check for signed left shift overflow. The rules for the
latter are a little subtle:
* neither C89 nor C++98 specify the behavior of a signed left shift at all
* in C99 and C11, shifting a 1 bit into the sign bit has undefined behavior
* in C++11, with core issue 1457, shifting a 1 bit *out* of the sign bit has
undefined behavior
As of this change, we use the C99 rules for all C language variants, and the
C++11 rules for all C++ language variants. Once we have individual
-fcatch-undefined-behavior= flags, this should be revisited.
llvm-svn: 162634
As part of this, pull together trapv handling into the same enum.
This also add support for NSW multiplies.
This also makes PCH disagreement on overflow behavior silent, since it
really doesn't matter except for warnings and codegen (no macros get
defined etc).
llvm-svn: 106956
Eli Friedman