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0 pointsmoosingin3space5y ago0 comments

For one, respected community member pcwalton has argued against compiling to C, citing the difficulty in producing performant, memory-safe output.

For another, from personal experience, I can comment that compiling to C in such a way that doesn't leak abstractions left and right is quite challenging. It's pretty hard to produce memory-safe C, so it's a ton of work, and the payoff is pretty marginal, as the most important platforms already are supported by LLVM.

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CyberRabbi5y ago

Automatically generating “memory safe” C is no harder than automatically generating “memory safe” LLVM bitcode.

brundolf5y ago

I think the issue is all of C's undefined behavior

ghoward5y ago

For the most part, that can be worked around as well, with careful use of unsigned arithmetic. See https://git.yzena.com/Yzena/Yc/src/branch/master/include/yc/... for some examples. All arithmetic is unsigned, but I use it to simulate 2's complement signed.

CyberRabbi5y ago

That is not difficult to avoid if you are generating short primitives. You can for the most part just convert the LLVM bitcode that the Rust compiler would output to the equivalent C snippet. Since each snippet is short, you can trivially check if it invokes undefined behavior. LLVM bitcode also can exhibit undefined behavior.

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0 pointsmoosingin3space5y ago0 comments

For one, respected community member pcwalton has argued against compiling to C, citing the difficulty in producing performant, memory-safe output.

0 comments

CyberRabbi5y ago

Automatically generating “memory safe” C is no harder than automatically generating “memory safe” LLVM bitcode.

brundolf5y ago

I think the issue is all of C's undefined behavior

ghoward5y ago

CyberRabbi5y ago

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