Aligning section contents is not required, but only
recommended, by the specification. Microsoft's documentation says
"For object files, the value should be aligned on a 4-byte boundary
for best performance."
However, according to my measurements, aligning section contents has
a neutral to negative effect on performance.
I measured the median run time of 100 links of Chromium's
base_unittests on Linux with lld-link and on Windows with link.exe with
both aligned and unaligned sections. On Linux I didn't see a measurable
performance difference, and on Windows the link was slightly faster
with unaligned sections (presumably because on Windows the bottleneck
Also, the sections created by cl.exe are unaligned, so we should expect
tools to broadly accept unaligned sections.