43 lines
1.5 KiB
Markdown
43 lines
1.5 KiB
Markdown
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# [bootstrap](../README.md) stage 05
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This stage consists of a C compiler capable of compiling TCC (after some modifications
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to TCC's source code).
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Run
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```
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make
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```
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to build our C compiler and TCC. This will take some time (approx. 25 seconds on my computer).
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A test program, `test.out` will be compiled using `tcc`. If you run
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it, you should get the output
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```
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Hello, world!
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```
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So now we just compile TCC with itself, and we're done, right?
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Well, not quite...
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## the nightmare begins
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The issue here is that to compile TCC/GCC with TCC, we need libc, the C standard library functions.
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Our C compiler just includes these functions in the standard header files, but normally
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the code for them is located in a separate library file (called something like
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`/usr/lib/x86_64-linux-gnu/libc-2.31.so`).
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This library file is itself compiled from C source files (typically glibc).
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So, can't we just compile glibc with TCC, then compile TCC with itself?
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Well, no. Compiling glibc with TCC is basically impossible; you need to compile
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it with GCC.
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Other libc implementations aren't too happy about TCC either -- I tried to compile
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[musl](http://www.musl-libc.org/) for several hours, and had to give up in the end.
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It seems that the one option left is to make our own libc, and try to use it along with
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TCC to compile GCC.
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From there, we should be able to compile glibc with GCC. Then, we can compile GCC with GCC and glibc.
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If we do all this, we should get the same libc.so and gcc files as if we had started
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with any GCC and glibc builds. It's all very confusing.
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