cmd/go: fix go command fails to perform concurrent compilation

CL 344909 fixed the bug in the order of passing gcflags from cmd/go to
cmd/compile. In that process, we merged the flags passed by cmd/go and
the flags specified by "-gcflags" to one variable. That causes the
gcBackendConcurrency function fails to detect concurrency level, since
when it expects only the latter flags.

To fix this, just don't merge those two variables, so we can now
correctly detect the concurrency level and passing the right -c to
the compiler.

Fixes #48490

Change-Id: I1293a7d6b946b7fccdd5cd34a38452bf6306e115
Trust: Cuong Manh Le <>
Run-TryBot: Cuong Manh Le <>
TryBot-Result: Go Bot <>
Reviewed-by: Bryan C. Mills <>
2 files changed
tree: 4ae29b239292887e04cf1b105b4fef82df5fd0b9
  1. .gitattributes
  2. .github/
  3. .gitignore
  11. api/
  12. codereview.cfg
  13. doc/
  14. lib/
  15. misc/
  16. src/
  17. test/

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