Hi, > While I was trying to install PostgreSQL from the git repository to start > contributing I faced this issue. When I try to type ./configure it gives me > this error > > checking for a thread-safe mkdir -p... /usr/bin/mkdir -p > checking for bison... /c/GnuWin32/bin/bison > configure: using bison (GNU Bison) 2.4.1 > checking for flex... configure: error: > *** The installed version of Flex, /c/GnuWin32/bin/flex, is too old to use > with PostgreSQL. > *** Flex version 2.5.35 or later is required, but this is > C:\GnuWin32\bin\flex.exe version 2.5.4. > > Look at the last two lines, the error says that the installed version of flex > is too old and is 2.4 which is correct and not too old and should be valid > but actually I can't proceed beyond this point. And I double checked the > version of flex > > $ flex --version > C:\GnuWin32\bin\flex.exe version 2.5.4 > > and made sure that it is properly included in PATH > > $ which flex > /c/GnuWin32/bin/flex
Flex 2.5.4 is ancient. Version 2.5.39 was released in 2020 and I didn't look further to figure out the exact release year of 2.5.4 You need something like flex 2.6.4 and bison >= 2.3. That's what I use. -- Best regards, Aleksander Alekseev
