where is the source code generate crtbegin.o (i386)?

[zet]

Hello, all

where is the source code which generate crtbegin.o (i386)?

gcc-6.2.0-source/libgcc/config/i386 only have ctr1.S/crtn.S, where is
the others(crtbegin/crtend/crt1, etc)?


thx

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