Delphi: .exe with built-in packages: 600kb, .exe + external BPLs: 6MB. Why is that?

bpl, delphi, exe

Solution

Because if you run a normal compile, the linker can do "smart linking" on the DCUs and remove code that your program never needs. But the packages are prebuilt and have all the code included, so you can't smartlink them down to a smaller size.

Problem

if I compile .exe file in delphi with built-in packages, it generates about 600kb EXE file. However if I compile it with runtime packages, the sum of sizes (.exe + all required .BPLs) is about 6-8 MB (depending on version of compiler). Why is the difference so significant?

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