Why are the random numbers all the same with MSYS2?

问题

I am trying to generate random numbers using std::random_device but each time I run the program they are the same. I tried the same code using an online IDE and it ran as expected. According to an answer here, this is a bug in Cygwin and MSYS2.

How can I upgrade MSYS2? I tried running the commands pacman -Syu and pacman -Su in its terminal but it had errors:

MSYS ~ $ pacman -Syuu error: mingw32: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" is unknown error: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" could not be looked up
remotely error: mingw64: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" is unknown error: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" could not be looked up
remotely error: msys: key "4A6129F4E4B84AE46ED7F635628F528CF3053E04"
is unknown error: key "4A6129F4E4B84AE46ED7F635628F528CF3053E04" could
not be looked up remotely :: Synchronizing package databases... 
mingw32                  472.5 KiB   305K/s 00:02
[#####################] 100%  mingw32.sig              438.0   B 
0.00B/s 00:00 [#####################] 100% error: mingw32: key "4A6129F4E4B84AE46ED7F635628F528CF3053E04" is unknown error: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" could not be looked up
remotely error: failed to update mingw32 (invalid or corrupted
database (PGP signature))  mingw64                  475.0 KiB   346K/s
00:01 [#####################] 100%  mingw64.sig              438.0   B
0.00B/s 00:00 [#####################] 100% error: mingw64: key "4A6129F4E4B84AE46ED7F635628F528CF3053E04" is unknown error: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" could not be looked up
remotely error: failed to update mingw64 (invalid or corrupted
database (PGP signature))  msys                     189.8 KiB   164K/s
00:01 [#####################] 100%  msys.sig                 438.0   B
0.00B/s 00:00 [#####################] 100% error: msys: key "4A6129F4E4B84AE46ED7F635628F528CF3053E04" is unknown error: key
"4A6129F4E4B84AE46ED7F635628F528CF3053E04" could not be looked up
remotely error: failed to update msys (invalid or corrupted database
(PGP signature)) error: failed to synchronize all databases

Is there any alternatives or work around for generating random numbers on Windows?

回答1:

I got it to work by referring to this news page on MSYS2. I had to run pacman -Sydd pacman before the rest of the steps could work.

来源：https://stackoverflow.com/questions/63201980/why-are-the-random-numbers-all-the-same-with-msys2