A command line tool and library for transferring data with URL syntax, supporting DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET, TFTP, WS and WSS. libcurl offers a myriad of powerful features
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Viktor Szakats 38107d3354
configure: fix --with-ngtcp2=<path> option for crypto libs
ngtcp2 1.14.0 added module dependencies to `ngtcp2_crypto_*.pc` files.
This broke certain build cases in curl, because configure was is
querying pkg-config modules by setting `PKG_CONFIG_LIBDIR` to the
directory specified via `--with-*=` options, including `--with-ngtcp2=`.
Setting `PKG_CONFIG_LIBDIR` tells pkg-config (and pkgconf) to ignore
system locations. This caused that `ngtcp2_crypto_gnutls.pc` could no
longer find its indirect dependencies, if those were present at system
locations (where they typically are). Another fallout was BoringSSL,
because it does not provide `openssl.pc` on its own, and successful
detection relied on finding a non-BoringSSL copy, typically at a system
location (also fixed in ngtcp2 main branch).

Fix `ngtcp2_crypto_*` detections to not touch `PKG_CONFIG_LIBDIR` and
instead prepend `<path>` set via `--with-ngtcp2=` to `PKG_CONFIG_PATH`.
This ensures to pick up any dependent modules from system locations.

Note the side-effect is that potentially undesired modules may be
detected this way from system locations, i.e. it makes this particular
detection less "hermetic" than the rest used in curl configure.

(Configurations using a bare `--with-ngtcp2` with no path were not
affected, and served as a workaround before this patch. It remains a
valid way of configuration after.)

Both `pkgconf` and `pkg-config` use this logic to calculate their search
directory list:
```pseudo
search = {}
if PKG_CONFIG_PATH is set
  search += PKG_CONFIG_PATH
endif
if PKG_CONFIG_LIBDIR is set (even if empty)
  search += PKG_CONFIG_LIBDIR
else
  search += built-in-pkg-config-dirs
endif
```

Refs:
https://github.com/curl/curl/pull/18028/commits (earlier attempt. Failed due to using `PKG_CONFIG_DIR` instead of the correct `PKG_CONFIG_PATH`)
https://github.com/curl/curl/pull/18028/commits/c0874ce8242d42a1ae1d570d6b70b8360da56482
https://man.archlinux.org/man/pkgconf.1.en
https://manpages.debian.org/unstable/pkgconf/pkgconf.1.en.html
https://manpages.debian.org/unstable/pkg-config/pkg-config.1.en.html
10e27fd63c

Bug: https://github.com/curl/curl/pull/18022#issuecomment-3120587041
Bug: https://github.com/ngtcp2/ngtcp2/pull/1689#issuecomment-3120593664
Follow-up to 04d90b5deb #20931
Follow-up to 3c64ffaff4 #18415 #18188
Follow-up to 99500660af #18028 #18022

Closes #20920
2026-03-17 14:37:53 +01:00
.circleci runtests: detect bad libssh differently for test 1459 (fixing CircleCI libssh job) 2025-11-16 23:28:44 +01:00
.github configure: fix --with-ngtcp2=<path> option for crypto libs 2026-03-17 14:37:53 +01:00
CMake cmake: rework binutils ld hack to not read LOCATION property 2026-03-16 13:32:39 +01:00
docs configure: fix --with-ngtcp2=<path> option for crypto libs 2026-03-17 14:37:53 +01:00
include RELEASE-NOTES: synced 2026-03-11 08:49:39 +01:00
lib openssl: drop obsolete SSLv2 logic 2026-03-17 14:36:54 +01:00
LICENSES krb5: drop support for Kerberos FTP 2025-09-20 23:58:28 +02:00
m4 build: drop openssl module dependency for BoringSSL from libcurl.pc 2026-03-17 00:42:41 +01:00
projects os400sys: fix typo in comment (symetry -> symmetry) 2026-03-15 12:00:08 +01:00
scripts mk-ca-bundle.pl: make generated timestamps deterministic 2026-03-16 11:59:59 +01:00
src tool_cb_wrt: fix no-clobber error handling 2026-03-16 15:31:44 +01:00
tests url: don't assume all transfers have hostnames 2026-03-17 10:26:35 +01:00
.clang-tidy.yml tidy-up: miscellaneous 2026-03-09 11:35:19 +01:00
.dir-locals.el copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
.editorconfig .editorconfig: add 2025-09-02 08:36:40 +02:00
.git-blame-ignore-revs copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
.gitattributes winbuild: MS-DOS batch tidy-ups 2024-07-02 19:26:15 +02:00
.gitignore build: drop the winbuild build system 2025-09-20 01:20:25 +02:00
.mailmap mailmap: Hamza Bensliman 2026-02-26 20:07:23 +01:00
acinclude.m4 configure: fix --with-ngtcp2=<path> option for crypto libs 2026-03-17 14:37:53 +01:00
appveyor.sh tidy-up: miscellaneous 2026-03-09 11:35:19 +01:00
appveyor.yml appveyor: minor improvements [ci skip] 2026-02-27 16:04:21 +01:00
buildconf copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
CHANGES.md CHANGES: fix typo in filename 2026-01-01 12:20:10 +01:00
CMakeLists.txt build: drop openssl module dependency for BoringSSL from libcurl.pc 2026-03-17 00:42:41 +01:00
configure.ac configure: fix --with-ngtcp2=<path> option for crypto libs 2026-03-17 14:37:53 +01:00
COPYING COPYING: bump copyright year range to 1996 - 2026 2026-01-08 23:19:44 +01:00
curl-config.in autotools: tidy-up if expressions 2025-12-10 22:29:19 +01:00
Dockerfile Dockerfile: update debian:bookworm-slim digest to 74d56e3 2026-03-03 01:36:55 +01:00
GIT-INFO.md REUSE: add copyright header to two files 2025-11-03 16:08:52 +01:00
libcurl.pc.in configure: do not echo most inherited LDFLAGS to config files 2024-11-14 09:55:45 +01:00
Makefile.am build: hook up badwords check to lint targets 2026-03-12 01:25:42 +01:00
README BUG-BOUNTY.md: we stop the bug-bounty end of Jan 2026 2026-01-26 08:26:28 +01:00
README.md README: add MQTTS 2026-02-05 22:55:01 +01:00
RELEASE-NOTES RELEASE-NOTES: fix typo 2026-03-13 10:25:27 +01:00
renovate.json renovate: merge two custom regex rules, escape dots 2026-01-23 15:58:16 +01:00
REUSE.toml badwords: avoid 'simply' 2026-03-10 19:34:06 +01:00
SECURITY.md stop using the word 'just' 2026-03-03 15:30:22 +01:00

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