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)
3.4 KiB
Vendored
Generated
splay
#include "splay.h"
This is an internal module for splay tree management. A splay tree is a binary search tree with the additional property that recently accessed elements are quick to access again. A self-balancing tree.
Nodes are added to the tree, they are accessed and removed from the tree and it automatically rebalances itself in each operation.
libcurl use
libcurl adds fixed timeout expiry timestamps to the splay tree, and is meant to scale up to holding a huge amount of pending timeouts with decent performance.
The splay tree is used to:
- figure out the next timeout expiry value closest in time
- iterate over timeouts that already have expired
This splay tree rebalances itself based on the time value.
Each node in the splay tree points to a struct Curl_easy. Each Curl_easy
struct is represented only once in the tree. To still allow each easy handle
to have a large number of timeouts per handle, each handle has a sorted linked
list of pending timeouts. Only the handle's timeout that is closest to expire
is the timestamp used for the splay tree node.
When a specific easy handle's timeout expires, the node gets removed from the splay tree and from the handle's linked list of timeouts. The next timeout for that handle is then first in line and becomes the new timeout value as the node is re-added to the splay.
Curl_splay
struct Curl_tree *Curl_splay(struct curltime i, struct Curl_tree *t);
Rearranges the tree t after the provide time i.
Curl_splayinsert
struct Curl_tree *Curl_splayinsert(struct curltime key,
struct Curl_tree *t,
struct Curl_tree *node);
This function inserts a new node in the tree, using the given key
timestamp. The node struct has a field called ->payload that can be set to
point to anything. libcurl sets this to the struct Curl_easy handle that is
associated with the timeout value set in key.
The splay insert function does not allocate any memory, it assumes the caller has that arranged.
It returns a pointer to the new tree root.
Curl_splaygetbest
struct Curl_tree *Curl_splaygetbest(struct curltime key,
struct Curl_tree *tree,
struct Curl_tree **removed);
If there is a node in the tree that has a time value that is less than the
provided key, this function removes that node from the tree and provides it
in the *removed pointer (or NULL if there was no match).
It returns a pointer to the new tree root.
Curl_splayremove
int Curl_splayremove(struct Curl_tree *tree,
struct Curl_tree *node,
struct Curl_tree **newroot);
Removes a given node from a splay tree, and returns the newroot
identifying the new tree root.
Note that a clean tree without any nodes present implies a NULL pointer.
Curl_splayset
void Curl_splayset(struct Curl_tree *node, void *payload);
Set a custom pointer to be stored in the splay node. This pointer is not used
by the splay code itself and can be retrieved again with Curl_splayget.
Curl_splayget
void *Curl_splayget(struct Curl_tree *node);
Get the custom pointer from the splay node that was previously set with
Curl_splayset. If no pointer was set before, it returns NULL.