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Am 15.02.2019 um 08:40 schrieb ingo:
> compiling with the wrong compiler and wrong option creates no errors and
> a program that won't run but you don't notice because the test file test
> is not called but test (check file types and compare values) that is
> already present on the system...
Oh yeah - that's a good one :)
Even better than trying to judge the run-time performance of certain
code under optimization, and typing `g++ -o3 -ffast-math -o test
test.cpp` instead of `g++ -O3 -ffast-math -o test test.cpp`...
> But, the proper results are in:
>
> FreeBSD Clang 6.0
> Delay 1
> 0.000u 0.005s 0:01.07 0.0% 0+0k 2+0io 0pf+0w
>
> Delay 10
> 0.000u 0.006s 0:10.64 0.0% 0+0k 6+0io 15pf+0w
>
> Delay 100
> 0.000u 0.005s 1:46.24 0.0% 0+0k 2+0io 0pf+0w
That's 1.07 ms, 10.64 ms and 106.24 ms, respectively, which makes a lot
more sense :)
> Mingwin g++.exe (Rev1, Built by MSYS2 project) 8.2.1 20181207
> Delay 1
> real 0m15.822s
> user 0m0.000s
> sys 0m0.015s
>
> Delay 10
> real 0m15.759s
> user 0m0.000s
> sys 0m0.031s
>
> Delay 100
> real 1m49.566s
> user 0m0.015s
> sys 0m0.031s
>
> ingo
That, too, makes sense, and indicates that MinGW has a minimum wait of
ca. 15 ms (on average at any rate). Which is fine, as C++11 allows
implementations to wait longer than requested (but not less).
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