Add missing <cstdint> and <cstddef> headers.

[breyerml]

This PR fixes a bug introduced in #188 due to not adding the necessary <cstdint> headers when using inptr_t.

Additionally, as far as I understand the code, the current develop branch exhibits UB or, at best, implementation-defined behavior due to the new error checking introduced in #186. If I only enable, for example, the triad kernel, goldC is never written and, therefore, is equal to 0 (the value of startC in the Stream.h header). However, later, the error is calculate as

T eC = std::fabs(vC - goldC) / std::fabs(goldC);

, which results in a division by zero and sets eC to NaN. In the check function, eC is tested against NaN and reports a failing check, although vC is also zero, in which case the result should be marked as correct.
I added a (ugly) hotfix, but I'm currently unable to implement a better fix due to time constraints.

[breyerml]

Also, if I run:

./omp-stream -s 10000000000 -n 2 --only Triad

all I get is a SegFault.
However, running it with

./omp-stream -s 1000000000 -n 2 --only Triad

gives to correct result.

(Note that our machine has enough RAM for the first call.)

[breyerml]

Ok. The problem with this SegFault is that due to the read_arrays function, the STREAM data must be stored twice. Therefore, we actually have 6 * sizeof(T) * array_size instead of 3 * sizeof(T) * array_size, which is kind of unintuitive, to say the least.

[tomdeakin]

Ok. The problem with this SegFault is that due to the read_arrays function, the STREAM data must be stored twice. Therefore, we actually have 6 * sizeof(T) * array_size instead of 3 * sizeof(T) * array_size, which is kind of unintuitive, to say the least.

This is a requirement because some models need to own their own data, either intrinsically or for performance reasons. Ideally we'd not need two copies, so would need to migrate all checking routines to each model. See #128

[tomdeakin]

I'm not sure I understand your comments, as goldC etc are initialised no matter what mode is run.

BabelStream/src/main.cpp

Line 518 in 2f00dfb

T goldC = startC;

OK, the problem is only with goldC because it is initialised to zero. I think we need a nicer solution to ensure that this is checked properly.

[tomdeakin]

I'm not sure I understand your comments, as goldC etc are initialised no matter what mode is run.

BabelStream/src/main.cpp

Line 518 in 2f00dfb

T goldC = startC;

OK, the problem is only with goldC because it is initialised to zero. I think we need a nicer solution to ensure that this is checked properly.

Also fixed in #202