Fix left shift operator undefined behavior in integer_ops

[joselopeqti]

As per the C++ Programming Reference page n0: 151, section: 7.6.7 Shift operators
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/n5001.pdf

The operands shall be prvalues of integral or unscoped enumeration type and integral promotions are performed. The type of the result is that of the promoted left operand. The behavior is undefined if the right operand is negative, or greater than or equal to the width of the promoted left operand.

[bashbaug]

Darn, I remember trying hard to avoid undefined behavior when we first did these tests (#1232), but I guess we missed this case.

Out of curiosity, how did you find this?

[svenvh]

Out of curiosity, how did you find this?

On current main, I can reproduce the issue locally by compiling the CTS with -fsanitize=undefined.

[bashbaug]

I can reproduce the issue locally by compiling the CTS with -fsanitize=undefined.

Nice, I was able to reproduce this also and verify that it no longer occurs with the fix in this PR.

Not in this PR, but should we have an option to build with the undefined behavior sanitizer enabled? We have a similar option for the thread sanitizer:

OpenCL-CTS/CMakeLists.txt

Lines 28 to 32 in 4a923c0

	option(SANITIZER_THREAD "Build with the thread sanitiser" OFF)
	if (SANITIZER_THREAD)
	add_compile_options(-fsanitize=thread)
	add_link_options(-fsanitize=thread)
	endif (SANITIZER_THREAD)

[bashbaug]

This has two approvals now and should be non-controversial. Merging.

[svenvh]

Not in this PR, but should we have an option to build with the undefined behavior sanitizer enabled?

Sorry for the late followup, but yes, I think that's valuable. I've opened #2672 for this.