[flang] [llvm] [flang-rt] Runtime implementation of extended intrinsic function SECNDS() (PR #152021)

[Eugene Epshteyn via llvm-commits]

eugeneepshteyn wrote:

> The atomic compare & swap if zero would be the initialization, I mean.

Ah, ok, at the cost of possible extra "midnight" computations. I'll try that.

https://github.com/llvm/llvm-project/pull/152021