Alexander J. Semenuk
5d5e35fb9b
## Problem Windows builds break with a current local toolchain (Scoop LLVM 22.1.8, CMake 4.4.0, VS 2026), in two independent ways: 1. The build stops at curl's deliberate guard: `#error "no non-blocking method was found/used/set"` in `third-party/curl/lib/nonblock.c`. 2. From the second configure onward, `cmake --build` re-runs CMake in an endless loop (observed 42 consecutive reconfigure cycles in a single build). Likely the same mechanism behind the "endlessly building" VS 2026 note in `docs/setup/dev/vs.md`. ## Root cause 1. `third-party/curl/CMake/CurlTests.c` passes `int *` to `ioctlsocket()`, whose third parameter is `u_long *`. Clang 22 promotes `-Wincompatible-pointer-types` to a hard error in C, so the `HAVE_IOCTLSOCKET_FIONBIO` try_compile silently fails and `curl_config.h` never defines it. Upstream CI does not see this because the windows-2022 runner image ships an older LLVM. GCC 14 promotes the same warning to a hard error, which is very likely the `CurlTests.c.obj` failure reported from MSYS2 in open-goal/jak-project#3551. Upstream curl hit the identical problem with GCC 14 and fixed the probe in curl 8.8.0 (curl/curl#13578). 2. The root CMakeLists copies the build tree's `compile_commands.json` into `<src>/build/` for clangd using `configure_file()`, which registers its input as a configure dependency. CMake rewrites `compile_commands.json` late in every generation, after `CTestTestfile.cmake` and `cmake_install.cmake` (outputs of the same Ninja regen rule), so once the dependency is registered the rule is deterministically dirty and every `ninja` invocation re-runs CMake. A pristine first configure is safe (the file does not exist yet, so the `if(EXISTS ...)` guard skips the copy), which is why the loop looks machine- or IDE-specific. ## Fix 1. Per review, re-vendor `third-party/curl` at the `curl-8_21_0` tag (previously `curl-8_3_0`), which carries the upstream probe fix plus two years of upstream development; `vendor.yaml` updated to match. Adjustments the version jump forced: - curl 8.15 removed the native macOS Secure Transport backend (`CURL_USE_SECTRANSP`), so macOS now builds curl against OpenSSL like Linux. The two macOS workflows install Homebrew `openssl@3` and export `OPENSSL_ROOT_DIR` (keg-only), and the macOS setup docs gained the same two lines. - `CURL_BROTLI` / `CURL_ZSTD` switched to AUTO-detection in curl 8.10; pinned OFF to keep the previous no-compression behavior and avoid silently linking whatever the CI images happen to have. - curl's new top-level `BUILD_EXAMPLES` cache option (default ON) leaked into discord-rpc's identically named option and broke configure at a nonexistent `examples/send-presence` directory; pinned OFF ahead of the third-party subdirectories. The diff is dominated by the mechanical tag-tree swap under `third-party/curl` (linguist-vendored, collapsed in review). The hand-written changes are `CMakeLists.txt`, the two macOS workflows, `docs/setup/system/macos.md`, and `vendor.yaml`. 2. Swap `configure_file()` for `file(COPY ...)`: the same clangd copy with no configure dependency registered. (`file(COPY_FILE ... ONLY_IF_DIFFERENT)` would be cleaner still but requires CMake 3.21, above the declared `cmake_minimum_required(VERSION 3.10)`.) ## Test plan - [x] Fresh `cmake --preset Release-windows-clang` (LLVM 22, no cache seeding) completes and logs `Enabled SSL backends: Schannel`; the FIONBIO probe passes without the previous `#error` - [x] Full Windows Release build from scratch in the branch worktree (all 1422 targets) - [x] goalc-test suite: 1509 passed, 0 failed - [x] Second consecutive configure with `compile_commands.json` present: the regen rule in `build.ninja` has no `compile_commands.json` input; `<src>/build/compile_commands.json` is still refreshed for clangd - [x] Repeated `ninja` invocations after a full build no longer re-run CMake - [x] macOS Intel and ARM CI green (first exercise of the OpenSSL backend switch) --- I work off a self-hosted forge, so this GitHub account is quiet; the configure logs and ninja dirty-node traces from the investigation are available if anyone wants the raw data. (AI-assisted)
3.2 KiB
Vendored
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c, SPDX-License-Identifier, Title, Section, Source, See-also, Protocol, Added-in
| c | SPDX-License-Identifier | Title | Section | Source | See-also | Protocol | Added-in | ||
|---|---|---|---|---|---|---|---|---|---|
| Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. | curl | libcurl-env | 3 | libcurl |
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NAME
libcurl-env - environment variables libcurl understands
DESCRIPTION
libcurl reads and understands a set of environment variables that if set controls and changes behaviors. This is the full list of variables to set and description of what they do. Also note that curl, the command line tool, supports a set of additional environment variables independently of this.
[scheme]_proxy
When libcurl is given a URL to use in a transfer, it first extracts the scheme part from the URL and checks if there is a given proxy set for that in its corresponding environment variable. A URL like https://example.com makes libcurl use the http_proxy variable, while a URL like ftp://example.com uses the ftp_proxy variable.
These proxy variables are also checked for in their uppercase versions, except the http_proxy one which is only used lowercase. Note also that some systems (like Windows) have a case insensitive handling of environment variables and then of course HTTP_PROXY still works.
An exception exists for the WebSocket ws and wss URL schemes, where libcurl first checks ws_proxy or wss_proxy but if they are not set, it falls back and tries the http and https versions instead if set.
ALL_PROXY
This is a setting to set proxy for all URLs, independently of what scheme is being used. Note that the scheme specific variables overrides this one if set.
CURL_SSL_BACKEND
When libcurl is built to support multiple SSL backends, it selects a specific backend at first use. If no selection is done by the program using libcurl, this variable's selection is used. Setting a name that is not a built-in alternative makes libcurl stay with the default.
SSL backend names (case-insensitive): GnuTLS, mbedTLS, OpenSSL, Rustls, Schannel, wolfSSL
HOME
When the netrc feature is used (CURLOPT_NETRC(3)), this variable is checked as the primary way to find the "current" home directory in which the .netrc file is likely to exist.
USERPROFILE
When the netrc feature is used (CURLOPT_NETRC(3)), this variable is checked as the secondary way to find the "current" home directory (on Windows only) in which the .netrc file is likely to exist.
NETRC
The filename used as netrc file when CURLOPT_NETRC(3) is used without CURLOPT_NETRC_FILE(3). (Added in 8.16.0)
NO_PROXY
This has the same functionality as the CURLOPT_NOPROXY(3) option: it gives libcurl a comma-separated list of hostname patterns for which libcurl should not use a proxy.
SSLKEYLOGFILE
When set and libcurl runs with an SSL backend that supports this feature, libcurl saves SSL secrets into the given filename. Using those SSL secrets, other tools (such as Wireshark) can decrypt the SSL communication and analyze/view the traffic.
These secrets and this file might be sensitive. Users are advised to take precautions so that they are not stolen or otherwise inadvertently revealed.
Debug Variables
Debug variables are intended for internal use and are documented in libcurl-env-dbg(3).