Hi Nazir, My problem got resolved after using the flex bison from the link you provided. Thank you so much!
Thanks and Regards, Prafulla On Mon, Jan 5, 2026 at 12:54 PM Prafulla Ranadive <[email protected]> wrote: > Hi Nazir, > > Thank you for your email. Sure, I will try using flex bison from link > shared by you. > I have stepped out for some personal work so I will be able to try out > only after 4 hours from now. > I will let you know as soon as I try that out. Once again thank you so > much. > > Regards, > Prafulla > > On Mon, 5 Jan, 2026, 12:09 pm Nazir Bilal Yavuz, <[email protected]> > wrote: > >> Hi, >> >> On Mon, 5 Jan 2026 at 08:28, Prafulla Ranadive >> <[email protected]> wrote: >> > >> > Hello, >> > >> > I have started exploring Postgresql recently. >> > I am trying to build Postgresql from source on a windows machine. I am >> referring to the page >> https://www.postgresql.org/docs/current/install-meson.html#INSTALL-SHORT-MESON >> > >> > The ninja command is failing with the error message: >> > >> > PS C:\PostgreSQLworkspace\postgres\build> ninja >> > [142/2102] Generating src/fe_utils/psqlscan with a custom command >> > FAILED: src/fe_utils/psqlscan.c >> > "C:\MyPrograms\Meson\meson.exe" "runpython" "../src/tools/pgflex" >> "--builddir" "." "--srcdir" ".." "--privatedir" "src/fe_utils/psqlscan.c.p" >> "--flex" "C:\MyPrograms\GnuWin32\bin\flex.EXE" "--perl" >> "C:\Strawberry\perl\bin\perl.EXE" "-i" "../src/fe_utils/psqlscan.l" "-o" >> "src/fe_utils/psqlscan.c" "--no-backup" "--" "-Cfe" "-p" "-p" >> > C:\MyPrograms\GnuWin32\bin\flex.EXE: can't open >> C:\PostgreSQLworkspace\postgres\build\src\fe_utils\psqlscan.c >> > [146/2102] Generating src/backend/bootstrap/bootscanner with a custom >> command >> > FAILED: src/backend/bootstrap/bootscanner.c >> > "C:\MyPrograms\Meson\meson.exe" "runpython" "../src/tools/pgflex" >> "--builddir" "." "--srcdir" ".." "--privatedir" >> "src/backend/bootstrap/bootscanner.c.p" "--flex" >> "C:\MyPrograms\GnuWin32\bin\flex.EXE" "--perl" >> "C:\Strawberry\perl\bin\perl.EXE" "-i" >> "../src/backend/bootstrap/bootscanner.l" "-o" >> "src/backend/bootstrap/bootscanner.c" >> > C:\MyPrograms\GnuWin32\bin\flex.EXE: can't open >> C:\PostgreSQLworkspace\postgres\build\src\backend\bootstrap\bootscanner.c >> > [147/2102] Generating src/backend/parser/scan with a custom command >> > FAILED: src/backend/parser/scan.c >> > "C:\MyPrograms\Meson\meson.exe" "runpython" "../src/tools/pgflex" >> "--builddir" "." "--srcdir" ".." "--privatedir" >> "src/backend/parser/scan.c.p" "--flex" >> "C:\MyPrograms\GnuWin32\bin\flex.EXE" "--perl" >> "C:\Strawberry\perl\bin\perl.EXE" "-i" "../src/backend/parser/scan.l" "-o" >> "src/backend/parser/scan.c" "--no-backup" "--" "-CF" "-p" "-p" >> > C:\MyPrograms\GnuWin32\bin\flex.EXE: can't open >> C:\PostgreSQLworkspace\postgres\build\src\backend\parser\scan.c >> > ninja: build stopped: subcommand failed. >> > PS C:\PostgreSQLworkspace\postgres\build> >> > >> > I have enabled full permission on the folder but still no luck. >> > >> > Can someone please help me with this? Any troubleshooting pointers >> would be a great help! >> >> Could you let me know where you downloaded flex from? I am wondering >> whether it might be this: >> https://gnuwin32.sourceforge.net/packages/flex.htm. >> >> For our Windows CI, we use flex and bison from this release instead: >> https://github.com/lexxmark/winflexbison/releases/tag/v2.5.24. >> >> If you have a chance, would you mind trying flex and bison from that >> source to see if it helps? >> >> -- >> Regards, >> Nazir Bilal Yavuz >> Microsoft >> >
