https://github.com/rust-lang/rust http://git.dreamy.place/mirrors/rust/atom?h=master 2025-09-29T01:32:14+00:00 2025-09-29T01:32:14+00:00 bors bors@rust-lang.org 2025-09-29T01:32:14+00:00 urn:sha1:772f380092b30680313b70a622cafc17f03e6bff Skip stack overflow handler for panic=immediate-abort std installs guard pages and a signal handler to ensure that stackoverflows 1) terminate abruptly and 2) print an nice message. Even for panic=immediate-abort, 1) is desirable, we don't want silent data corruption there. But 2) is completely unnecessary, as users deliberately *don't* want nice messages, they want minimum binary size. Therefore, skip the entire guard signal handler setup, which saves a lot of bytes. I tested this with a hello world binary using fat LTO, build-std, panic=immediate-abort, opt-level=s, strip=debuginfo. `size` reports significant savings: ``` text data bss dec hex filename 15252 1032 104 16388 4004 tiny-before 6881 964 48 7893 1ed5 tiny-after2 ``` `nm -U` goes from 71 to 56, getting rid of a bunch of stack overflow related symbols. The disk size goes from `31k` to `24k`. The impact on the error message is minimal, as the message was already missing. before: ``` fish: Job 1, './tiny-so-before' terminated by signal SIGABRT (Abort) ``` after: ``` fish: Job 1, './tiny-so-after' terminated by signal SIGSEGV (Address boundary error) ``` I didn't test the Windows part, but it likely also has savings. 2025-09-27T14:25:47+00:00 Jeremy Soller jackpot51@gmail.com 2025-09-27T14:25:47+00:00 urn:sha1:760ed37769c4902c97c874d324978472ce02f9ba 2025-09-27T12:16:06+00:00 Noratrieb 48135649+Noratrieb@users.noreply.github.com 2025-09-27T11:37:29+00:00 urn:sha1:660a3486fc6da2c3599a167d73d849178f98bc17 std installs guard pages and a signal handler to ensure that stackoverflows 1) terminate abruptly and 2) print an nice message. Even for panic=immediate-abort, 1) is desirable, we don't want silent data corruption there. But 2) is completely unnecessary, as users deliberately *don't* want nice messages, they want minimum binary size. Therefore, skip the entire guard signal handler setup, which saves a lot of bytes. I tested this with a hello world binary using fat LTO, build-std, panic=immediate-abort, opt-level=s, strip=debuginfo. `size` reports significant savings: ``` text data bss dec hex filename 15252 1032 104 16388 4004 tiny-before 6881 964 48 7893 1ed5 tiny-after2 ``` `nm -U` goes from 71 to 56, getting rid of a bunch of stack overflow related symbols. The disk size goes from `31k` to `24k`. The impact on the error message is minimal, as the message was already missing. before: ``` fish: Job 1, './tiny-so-before' terminated by signal SIGABRT (Abort) ``` after: ``` fish: Job 1, './tiny-so-after' terminated by signal SIGSEGV (Address boundary error) ``` 2025-09-25T17:36:14+00:00 Vadim Petrochenkov vadim.petrochenkov@gmail.com 2025-08-01T18:55:11+00:00 urn:sha1:f89660e4aa018401ca993f0df190e5f4c4a6799b I.e. do not mark them as used, or non-speculative loaded, or similar. Previously they were sometimes finalized during early resolution, causing issues like https://github.com/rust-lang/rust/pull/144793#issuecomment-3168108005. 2025-09-24T20:07:26+00:00 Stepan Koltsov stepan.koltsov@gmail.com 2025-09-24T19:32:50+00:00 urn:sha1:92859e98ee1a2101df8322a8581e4d638eb15078 2025-09-12T15:16:38+00:00 Ralf Jung post@ralfj.de 2025-09-12T15:16:38+00:00 urn:sha1:5d8e41b656fa2802c8ab52d4c72ad67e8ff345c2 This reverts commit 7ce620dd7c6fc3371290b40a1ea28146f0d37031. The const-hacks introduces bugs, and they make the code harder to maintain. Let's wait until we can constify these functions without changing their implementation. 2025-09-12T08:18:41+00:00 bors bors@rust-lang.org 2025-09-12T08:18:41+00:00 urn:sha1:ac4495a10db552483c0c0a0049962850ca4123c2 std: optimize `dlsym!` macro and add a test for it The `dlsym!` macro always ensures that the name string is nul-terminated, so there is no need to perform the check at runtime. Also, acquire loads are generally faster than a load and a barrier, so use them. This is only false in the case where the symbol is missing, but that shouldn't matter too much. 2025-09-10T13:34:38+00:00 joboet jonasboettiger@icloud.com 2025-09-09T11:17:45+00:00 urn:sha1:4c992199598b4fddc25d52f40fa3642c9e065e60 `dlsym` doesn't work for finding libc symbols on platforms like linux-musl, so the test will fail. 2025-09-10T13:26:17+00:00 joboet jonasboettiger@icloud.com 2025-08-09T17:07:08+00:00 urn:sha1:ad08577a503dfd03e308bd272e76d95e31c6d0ef 2025-09-08T15:02:25+00:00 joboet jonasboettiger@icloud.com 2025-08-29T16:01:02+00:00 urn:sha1:4b15dd5a84742f9e7641b62e490765e0c1cb415c