sha: restrict the x86 bswap asm to x86 - #41
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ByteReverse(word32) in src/sha.h uses the x86 `bswap` instruction via inline
asm, guarded only by `#if defined(__GNUC__)`. GCC and Clang define __GNUC__ on
every architecture they target, so on aarch64 the guard passes and the
assembler then rejects the instruction:
Error: unknown mnemonic `bswap' -- `bswap %eax'
This makes the tree fail to build on any ARM64 host -- Apple Silicon, ARM
servers, a Raspberry Pi -- at a point far from anything the user did.
Narrow the guard to the architectures where the instruction exists. The
portable C fallback directly below is then used everywhere else; it was
already there and already correct.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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…RM64 build (port of Bitflash-sh#41); gitignore: cover key files (port of Bitflash-sh#43) ## Bootstrap seeds (Bitflash-sh#36) A node with an empty cache has only the Nostr relays for discovery -- if those are down, blocked, or just slow, a first run has no way into the network at all, which is exactly the moment a user has the least patience. Seeds are the floor under that: a compiled-in list of long-lived peers, tried automatically only when the peer cache is empty. A seed entry is deliberately just an address and an encryption key, no meeting node -- the rendezvous relay pairs on the service's public key, and a .btf address is that key, so a seed is findable by walking the known relays. Recording which relay a seed was on would rot the moment it failed over, which is the exact "advertising a rendezvous nobody is registered at" failure this project has chased before. Seeds carry no special authority: they hand out the same signed, self-certifying descriptors any peer does, so a hostile seed can stall a bootstrap but can't forge a peer or feed a false chain. The compiled list here is empty, deliberately -- upstream shipped their own dedicated bootstrap node's address in their version of this commit, but that's their infrastructure, not something this fork has any relationship to or authority to point users at. /btfseed= ADDRESS:ENCHEX (repeatable, CLI-only) covers testing and private networks without needing a compiled entry. Adapted the hex-decode call to our own BtfPeerCacheHexToBytes rather than a generic HexToBytes upstream doesn't have under that name. ## ARM64 build failure (Bitflash-sh#41) ByteReverse(word32) in sha.h used the x86 bswap instruction via inline asm, guarded only by #if defined(__GNUC__) -- true on every architecture GCC/Clang target, so on aarch64 the assembler rejected the instruction outright. The 64-bit ByteReverse right below it already had the correct guard (&& defined(__x86_64__)); the 32-bit one just never got it. Fails the build on Apple Silicon, ARM servers, or a Raspberry Pi -- all plausible headless-node hosts. ## .gitignore gaps (Bitflash-sh#43) *.dat/wallet.dat were covered, but btf_enc.key (this node's .btf identity) and nostr.key (its Nostr signing key) are not .dat files and are exactly as sensitive -- already listed explicitly in our .gitignore from an earlier session, but walletrpc.token (bearer authority to spend from the wallet over the wallet API) was missing entirely, along with a general *.key catch-all and patterns for key backup archives, mempool dumps, and stray .patch/.rej/.orig files. A node run with its data directory inside a working tree -- the obvious thing to do while developing -- would otherwise leave all of this untracked but committable.
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Correct, and the file argues your case for you: the #if defined(__GNUC__) && defined(__x86_64__)
__asm__ ("bswap %0" : "=r" (value) : "0" (value));The Since 1280 real blocks validated from genesis, proof-of-work checks included, with no hash errors and no rejections. The x86 path is untouched, as intended. I have no ARM64 host to confirm the build failure directly, but the mechanism is not in doubt: GCC and Clang define Reviewed clean. |
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ByteReverse(word32) in src/sha.h uses the x86
bswapinstruction via inline asm, guarded only by#if defined(__GNUC__). GCC and Clang define GNUC on every architecture they target, so on aarch64 the guard passes and the assembler then rejects the instruction:This makes the tree fail to build on any ARM64 host -- Apple Silicon, ARM servers, a Raspberry Pi -- at a point far from anything the user did.
Narrow the guard to the architectures where the instruction exists. The portable C fallback directly below is then used everywhere else; it was already there and already correct.