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Re: [PATCH] Fix nrv-1.c false failure on aarch64.


On 10/18/2017 10:59 AM, Egeyar Bagcioglu wrote:
> Hello,
> 
> Test case "guality.exp=nrv-1.c" fails on aarch64. Optimizations reorder
> the instructions and cause the value of a variable to be checked before
> its first assignment. The following patch is moving the
> break point to the end of the function. Therefore, it ensures that the
> break point is reached after the assignment instruction is executed.
> 
> Please review the patch and apply if legitimate.
This seems wrong.

If I understand the test correctly, we want to break on the line with
the assignment to a2.i[4] = 7 and verify that before that line executes
that a2.i[0] == 42.

Moving the test point to the end of the function seems to defeat the
purpose of the test.  A breakpoint at the end of the function to test
state is pointless as it doesn't reflect what a user is likely to want
to do.

I'm guessing based on your description that optimization has sunk the
assignment to a2.i[0] down past the assignment to a2.i[4]?  What
optimization did this and what do the dwarf records look like?


Jeff


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