First, our original append line was completely ineffective; we never
used that "flags" slice again. Second, we only attempted to use the flag
when we obfuscated a package.
In fact, we never care about debugging information here, so for any
package we compile, we can add "-dwarf=false". At the moment, we compile
all packages, even if they aren't to be obfuscated, due to the lack of
access to the build cache.
As such, we save a significant amount of work. The numbers below were
obtained on a quiet machine with "go test -bench=. -benchtime=10x", six
times before and after the change.
name old time/op new time/op delta
Build-8 2.06s ± 4% 1.87s ± 2% -9.21% (p=0.002 n=6+6)
name old sys-time/op new sys-time/op delta
Build-8 1.51s ± 2% 1.46s ± 1% -3.12% (p=0.004 n=6+5)
name old user-time/op new user-time/op delta
Build-8 11.9s ± 2% 10.8s ± 1% -8.71% (p=0.002 n=6+6)
While at it, only do CI builds on pushes and PRs to the master branch,
so that my PRs created from the same repo don't trigger duplicate
builds.