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RE: Section (.sdata2) being omitted but SIZEOF(.sdata2) is not zero?

> Yes, I think you've nailed it (a nice debugging effort!).  We strip sections early
> based on their sizes before relaxation.  Your .sdata2 section is empty except
> for the padding, and the layout before relaxation just happens to need no
> padding.  After relaxation you need padding but the section with the padding
> has gone.  :-(

What are the chances we'd hit this!  It only happens if the expression that computes the amount of padding necessary to pad out .sdata2 to end on a 4KB page boundary decides that no padding is necessary, so about 1 chance in 4096, or since .text is probably always 4-byte aligned, 1 chance in 1024.  Must be our lucky day.  No wonder I couldn't reproduce this in a simple test case (especially because my attempt at doing so did not use any library code with .eh_frame sections that change size).  What I'm still not sure I understand is that we've seen this problem happen a few times over the last few months on a project with a fair amount of development ongoing.  I could maybe see us maybe hitting this once, but then after a bit of churn, the chances of hitting it again shortly afterwards should be even slimmer.

So I guess a simple workaround  is to add a ". = . + 4" inside .sdata2 before aligning, to force that section to always contain at least 4  bytes.

Thanks for your help,

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