I get the following:
Free Pascal Compiler version 3.0.4 [2020/04/11] for x86_64
Copyright (c) 1993-2017 by Florian Klaempfl and others
Target OS: Win64 for x64
Compiling .\project1.lpr
Linking project1.exe
project1.lpr(5,1) Error: Entrypoint _mainCRTStartup not defined
project1.lpr(5,1) Fatal: There were 1 errors compiling module, stopping
Fatal: Compilation aborted
Error: C:\lazarus\2.0.8\fpc\3.0.4\bin\x86_64-win64\ppcx64.exe returned an error exitcode
And with FPC 3.2.0 or newer I get the error that marcov mentioned.