Commit graph

715 commits

Author SHA1 Message Date
Graham Campbell
5bb7d7a4f2
http: stop dropping large custom headers
Closes #22336
2026-07-21 00:37:46 +02:00
Graham Campbell
f0f84d1251
http: avoid length underflow in Curl_compareheader
Closes #22338
2026-07-21 00:14:07 +02:00
Graham Campbell
820c014578 cfilters: fix event-based connection shutdown
- Adjust pollset during connection shutdown.

- Separate the FIRSTSOCKET and SECONDSOCKET check so that one being in
  connect or shutdown no longer adds poll events for the other.

- Fix shutdown state evaluation (as detailed below).

- Add a unit test for Curl_conn_adjust_pollset.

- Add a client for event testing.

- Test that shutdown sockets stay with the socket callback until done.

The pollset predicate now reads the connection's own shutdown state
rather than going through data->conn, and the EXPIRE_SHUTDOWN arming in
cshutdn_perform() works again: next_expire_ms started at 0 and could
never be set, so a peer that never sends a close_notify would still park
its connection forever, timeout or not.

Reported-by: pszemus@users.noreply.github.com

Fixes https://github.com/curl/curl/issues/22282
Closes https://github.com/curl/curl/pull/22304
2026-07-17 04:00:56 -04:00
Collin Funk
dfa444f1e5
unit3214: fix to pass on systems with >=128-bit pointers
E.g. on CHERI pointers are 128 bits [1]. This causes the unit3214 test
to fail, which was written with more traditional platforms in mind. Here
is the output of log/stderr3214:

```
URL: -
BAD: struct Curl_easy is 7984 bytes, allowed to be 5370: 2614 bytes too big
BAD: struct connectdata is 1408 bytes, allowed to be 1300: 108 bytes too big
BAD: struct Curl_multi is 1248 bytes, allowed to be 850: 398 bytes too big
BAD: struct curl_httppost is 224 bytes, allowed to be 112: 112 bytes too big
BAD: struct curl_slist is 32 bytes, allowed to be 16: 16 bytes too big
BAD: struct curl_khkey is 32 bytes, allowed to be 24: 8 bytes too big
BAD: struct curl_hstsentry is 48 bytes, allowed to be 40: 8 bytes too big
BAD: struct curl_mime is 144 bytes, allowed to be 96: 48 bytes too big
BAD: struct curl_mimepart is 592 bytes, allowed to be 440: 152 bytes too big
BAD: struct curl_certinfo is 32 bytes, allowed to be 16: 16 bytes too big
BAD: struct curl_tlssessioninfo is 32 bytes, allowed to be 16: 16 bytes too big
BAD: struct curl_blob is 32 bytes, allowed to be 24: 8 bytes too big
BAD: struct CURLMsg is 48 bytes, allowed to be 24: 24 bytes too big
BAD: struct curl_header is 80 bytes, allowed to be 48: 32 bytes too big
Test ended with result 14
```

Multiply the allowed size on systems with larger than 64-bit pointers.

[1] https://www.cl.cam.ac.uk/research/security/ctsrd/pdfs/20171017a-cheri-poster.pdf

Closes #22299
2026-07-14 03:14:49 +02:00
Graham Campbell
c3ae9ef822
hostip: only cache negative resolves for authoritative answers
Closes #22302
2026-07-13 11:27:16 +02:00
Alhuda Khan
c3f9ef13f6
mime: reject CR and LF in mail part name and filename
Closes #22247
2026-07-13 08:29:22 +02:00
Viktor Szakats
b093d88447
tidy-up: typos, comment nits
Closes #22294
2026-07-11 13:55:45 +02:00
Daniel Stenberg
69ac867f98
TLS: drop support for TLS-SRP
The options will simply do nothing.

Closes #21965
2026-07-04 12:20:20 +02:00
Viktor Szakats
39dec13ec0
build: always use local inet_pton()/inet_ntop() implementations
Also repurpose existing build-time feature checks into unit test 1961,
to verify.

Prior to this patch these functions were auto-detected with both
autotools and cmake. In case of autotools there was an extra
verification phase ensuring the functions work as expected. This step
required running the function, thus was limited to non-cross-builds. For
cross-builds and CMake it always used the system implementation if
present. On Windows it always used the local implementation, because
availability/use is complicated there.

After this patch all platforms, always use the local implementation,
which is known to be accurate. This makes curl behave more consistently,
and simplifies the build process, a fixes cross-builds and CMake
auto-detection differences.

Also:
- test1960: enable unconditionally.
- checksrc: disallow globally, allowlist in `block_ip.c` example.
- dnsd: verify ntop result for NULL before passing to printf.

Ref: https://github.com/curl/curl/pull/22137#issuecomment-4797440983
Ref: #22137
Ref: 8537a5b0bc #16577

Closes #22170
2026-06-27 01:24:39 +02:00
Viktor Szakats
84c5dcdb05
tidy-up: syntax and code nits
- cmp-pkg-config.sh: replace `-r -f` with `-rf` to match rest of repo.
- configure.ac: add double quotes for robustness (not a bug).
- curl-openssl.m4: merge nested `if`s.
- CurlTests.c: drop `!= 0`, also to sync with m4.
- CurlTests.c: replace `example.com` with `localhost` in
  `gethostbyname()` feature test code. (compile-only, not a bug)
- GHA/http3-linux: drop literal `true` from bool expression.
- lib650: drop redundant `&`.
- move variable/call to left-hand side of equality checks, where
  missing.
- perl: detach `<`/`>` from filename in `open()`, where missing.
- schannel: apply two nit fixes lost in rebase.
- scripts/verify-release: drop redundant double quotes.
- scripts/verify-release: exit with error code on error.
- synctime: replace magic numbers with `sizeof()`.
- telnet: add missing parentheses to macro value.
- tests/Makefile.am: use single quotes.
- tool_operate: drop redundant `break` after `return` in VMS code.
- unit2413: drop unused NULL pointer + free call.
- unit2413: fix duplicate test case name.
- urlapi: drop redundant parentheses.
- urlapi: drop `CURL_UNCONST()` that became redundant.

Closes #22186
2026-06-26 15:45:24 +02:00
Stefan Eissing
cfc7922377
altsvc: use Curl_peer in processing
Use `data->state.origin` when processing alt-avc information.

Decomplexify parsing function.

Closes #22184
2026-06-26 14:12:53 +02:00
Viktor Szakats
397b8f0ec6
tidy-up: docs, comments, typos, whitespace
- GHA/windows: mention `IgnoreStandardErrorWarningFormat=true`
  in comment.
- cmake: fix MIT/GNU GSS order in messages.
- drop some exclamation marks from messages.
- drop redundant ending newlines from messages.
- fold/unfold where possible.
- fix indent, whitespace, typos and other nits.

Closes #22185
2026-06-26 11:36:09 +02:00
Stefan Eissing
be1d976a2a
peer: fix ipv6 detection
When trying to detect ipv6 addresses, ipv4 addresses were also
flagged as ipv6.

Add test2413 to check.

Closes #22134
2026-06-22 17:16:07 +02:00
Daniel Stenberg
ab779d4e4a
doh: stricter HTTPS RNAME parsing
If any sublabel is longer than 63 octets, abort. This then also catches
compression attempts.

Verified in test 1658

Reported-by: netspacer.research
Closes #22124
2026-06-22 09:53:14 +02:00
Daniel Stenberg
e8e3af2abb
doh: cap the maximum TTL to 24 hours
To avoid mistakes or abuse to cause problems. Many public DNS providers
cap their cache times to this.

Verify in test 1650

Reported-by: netspacer.research
Closes #22122
2026-06-22 09:12:55 +02:00
Stefan Eissing
7333f6674c
cf-capsule: complete filter
Make the capsule filter complete, implement:

- pollset handling
- flush handling and querying
- shutdown handling
- replace allocated send buffer with a bufq

Closes #22019
2026-06-15 15:42:22 +02:00
Viktor Szakats
0ffab25b6c
tidy-up: miscellaneous
- `N byte` -> `N-byte` or `N bytes`.
- INTERNALS.md: language tweaks.
- schannel: language tweak in comment/error message.
- socks_gssapi, socks_sspi: simplify composing an error message.
  (at a cost of 8 extra constant string bytes.)
- m4/curl-compilers.m4: fix typo in link (in comment).
- contrithanks.sh: fix indent, drop stray `;` terminator.
- lib, src, tests: drop/fix a bunch of badwords.
- fix typos in comments.
- fix indent, stray spaces.

Some of these spotted by GitHub Code Quality and Copilot

Closes #22009
2026-06-14 20:10:28 +02:00
Stefan Eissing
73daec6620
lib: transfer origin and proxy handling
Add `data->state.origin` as the origin the transfer is sending the
current request to/gets the response from. Use it for request specific
properties like authentication, hsts and cookie handling, etc.

Unless talking to a forwarding HTTP proxy (e.g. not tunneling),
`data->state.origin` and `conn->origin` are the same.

With a forwarding HTTP proxy in play, `conn->origin` is set to
`conn->http_proxy.peer` and `conn->bits.origin_is_proxy` (a new bit) is
set.

Remove the connection bits, now replaced with:

* `conn->bits.socksproxy` -> `conn->socks_proy.peer`
* `conn->bits.httpproxy` -> `conn->http_proy.peer`
* `conn->bits.proxy` -> `(conn->socks_proy.peer || conn->http_proy.peer`)
* `conn->bits.tunnel_proxy` -> (`conn->http_proy.peer && !conn->bits.origin_is_proxy`)
* `(conn->bits.httpproxy && !conn->bits.tunnel_proxy)` -> `conn->bits.origin_is_proxy`

Rename `noproxy.[ch]` to `proxy.[ch]`. Move the connection proxy setup
code from `url.c` to `proxy.c`.

Remove `data->info.conn_remote_port` as no one uses it.

Add test_40_02b for a SOCKS connection to a forwarding HTTPS proxy.

Update internal documentation about peers and creds.

Closes #21967
2026-06-12 23:52:00 +02:00
Stefan Eissing
30c9c79cf8
cf-socket: make Curl_addr2string static
Move as sockaddr2string() into cf-socket.c where its only callers are.

Mark as UNITTEST for unit1609.

Move "struct Curl_sockaddr_ex" into sockaddr.h, so connect.h and
cf-socket.h can be included without all the system headers needed.

Closes #21946
2026-06-11 08:15:31 +02:00
Viktor Szakats
97aed9c960
tidy-up: drop stray comparisons with literal zero
Drop from:
- strcmp, strcmpi, strncmp, memcmp, lstat, getrlimit, setrlimit, fseek,
  fstat
- autotools detection snippets.
- smooth-gtk-thread: simplify `!var != 0` expression.

Closes #21947
2026-06-10 15:15:54 +02:00
Viktor Szakats
2f3fa479dd
build: enable -Wformat-signedness, fix issues found
Adjust code to avoid `-Wformat-signedness` warnings, while making sure
that enums are always cast to a known type when passing them to `printf`
functions, to support compilers and compiler settings where enums are
not default-size signed ints.

- cast integers printed as hex to `unsigned`. (63 times, 20 of them in
  `mbedtls.c`)
- cast misc enums to `int` for printing. (31 times)
- cast `CURL_LOCK_DATA_*` enums to `int`. (4 times)
- cast `CURL_FORMADD_*` enums to `int`. (13 times)
- cast `CURLSHE_*` enums to `int`. (3 times)
- cast `CURLUE_*` enums to `int`. (33 times)
- cast `CURLMSG_*` enums to `int`. (6 times)
- cast `CURLE_*` enums to `int`. (~380 times)
- unit1675: fix mask.
  Follow-up to 7c34365cce #21879

Ref: #18343 (initial attempt)

Closes #20848
2026-06-10 15:14:08 +02:00
Stefan Eissing
f924489b25
ngtcp2: share common functionality
Share common functions/structs between ngtcp2 HTTP/3 and the proxy
version.

Fix bugs in proxy implementation when it comes to stream and pollset
handling and transfer lifetimes.

Curl_multi_xfer_sockbuf_borrow: work without multi

When a connection gets shutdown by a share, the easy handle used is
share->admin and it does not have a multi handle. In that case let
Curl_multi_xfer_sockbuf_borrow() allocate a buffer to be freed on
release.

This happens when a TLS filter sends its last notify through a HTTP/3
proxy tunnel.

Closes #21871
2026-06-10 13:28:05 +02:00
Viktor Szakats
014be82a66
tidy-up: drop redundant == NULL syntax
Where missed by checksrc.

Closes #21935
2026-06-09 14:37:36 +02:00
Viktor Szakats
59213abfb2
tidy-up: drop redundant != NULL syntax
Where missed by checksrc.

Closes #21932
2026-06-09 14:37:36 +02:00
Viktor Szakats
847aac066d
tidy-up: use uppercase TRUE/FALSE where missing
Keep it only in external API calls and C++ code.

Also:
- curlx/fopen: replace with `!!`.

Spotted by GitHub Code Quality in cf-socket.c.

Closes #21925
2026-06-09 12:52:08 +02:00
Viktor Szakats
bbb226b226
unit1675: fix potential memory leak on dynbuf fail path
Spotted by GitHub Code Quality

Closes #21922
2026-06-09 12:30:16 +02:00
Viktor Szakats
952b04474c
tidy-up: miscellaneous
- badwords: replace stray synonyms with 'null-terminator'.
- tests/FILEFORMAT.md: tidy up feature descriptions.
- printf: replace stray `%i` masks with `%d` for consistency.
- pytest: add comments for empty excepts to try silencing GitHub CodeQL
  warnings.
- tool1394, unit1675: merge nested `if`s.
- dnscache: fix typo in comment.
- fix whitespace, indent and newlines.

Closes #21921
2026-06-09 11:07:55 +02:00
Viktor Szakats
7c34365cce
urlapi: fix memleaks on error in parse_hostname_login()
Detected by GitHub Code Quality

Follow-up to acd82c8bfd #11006
Follow-up to 4183b8fe9a #8049

Closes #21879
2026-06-08 00:42:51 +02:00
Stefan Eissing
fbcf10ab84
progress: fx CURLINFO time reporting
Whack the times reported for a transfer (see
https://curl.se/libcurl/c/curl_easy_getinfo.html#TIMES) into order for
all variations of up-/download, http/ftp etc. Make sure they are
reported in the documented order.

There is still the *possibility* of PRETRANSFER being longer then
POSTTRANSFER, if a server sends a response before an upload is done.
POST is the time the first response byte is received, and PRE is the
time the last byte was sent by curl.

This may happen with more likelihood on HTTP/2 and 3 for a server
rejected upload. But for successful uploads, the answer will almost over
come afterwards.

Undo the previous twists in lib500.c tests, adjust pytest timeline
checks.

Fixes #21828
Reported-by: BazaarAcc32 on github
Closes #21843
2026-06-07 14:39:10 +02:00
Viktor Szakats
d3e9a815c4
tidy-up: miscellaneous
- fix typos.
- badword: add two new words.
- cpp: drop parentheses from standalone `#if` expressions.
- libssh: vertical-align comment block with others.
- clang-format.

Closes #21880
2026-06-05 16:57:38 +02:00
Stefan Eissing
22d979400a
vquic: moving related things into subdir
Move QUIC related implementations into the vquic directory. Rename
files that implement a connection filter accordingly.

Closes #21848
2026-06-02 22:48:21 +02:00
Viktor Szakats
89683e05b9
tidy-up: use test/example domains more
Closes #21849
2026-06-02 15:31:48 +02:00
Stefan Eissing
31cb54e1fa
cfilters: remove close method
closing a filter chain and reconnecting it again is a complication
that only the HTTP/1.x proxy filter used. Remove it from all filters.

Instead, a filter can return CURLE_AGAIN during the connect phase
and the cf-setup filter will tear down all "sub filters" and restart
over.

With this, a filter never resets to the initial phase but progresses
through connect -> connected -> shutdown -> destroy once.

Closes #21831
2026-06-02 08:27:00 +02:00
Viktor Szakats
4e98f6d225
units: drop redundant pointer check and workaround
All users of the `verify_memory()` macro used a fixed-length buffer for
the test output, which then needed a workaround to silence GCC
`-Waddress` warnings.

```
tests/unit/unit1615.c: In function 'test_unit1615':
tests/libtest/unitcheck.h:51:8: error: the address of 'output_buf' will always evaluate as 'true' [-Werror=address]
   51 |     if((dynamic) && memcmp(dynamic, check, len)) {                          \
      |        ^
tests/unit/unit1615.c:114:3: note: in expansion of macro 'verify_memory'
  114 |   verify_memory(output_buf, precomp_hash1, CURL_SHA512_256_DIGEST_LENGTH);
      |   ^~~~~~~~~~~~~
```

Drop redundant address check and the workarounds with it.

Closes #21833
2026-06-01 22:36:40 +02:00
Viktor Szakats
d229055549
tidy-up: miscellaneous
- drop more uses of the word "just". (not enforced here)
- drop some uses of the "will" word.
- "then" -> "than".
- tests/http/testenv/curl.py: fix copy-paste typo in error message.
- pytest: replace `shutdownh` with `shutdown` in test names.
  Spotted by GitHub Code Quality.
- comment typos.
- whitespace and newlines fixes.

Closes #21830
2026-06-01 22:33:57 +02:00
Stefan Eissing
d3391229b0
vtls_config: adjust to origin
When a transfer goes against another origin than the initial one, do not
add the following to the ssl configuration: client cert, client key, srp
user/pass, pinned key.

Closes #21695
2026-06-01 09:39:17 +02:00
Stefan Eissing
e4139a73c8
h3-proxy: fixes around H3 proxy
code:
- less exception handling in existing code
- true ip happy eyeballing
- enable certificate verification
- cf-h2-proxy: abort connection when server closed connection

tests:
- remove all --insecure and --proxy-insecure args
- make session reuse test_60_12 a working one
- resolve port conflicts between h2o and nghttpx
- use proxy args better
- make test_60_06 run shorter
- kill h2o at the end of tests, normal stop takes too long

Ref: 59213f8248 #21789
Follow-up to e78b1b3ecc #21153

Closes #21798
2026-05-28 14:41:27 +02:00
tiymat
f1959ae962
urlapi: fix an issue parsing file URLs
Fixes #21743
Closes #21764
2026-05-28 08:49:56 +02:00
Daniel Stenberg
d1b482caec
unit3400: repair after capsule_encap_udp_hdr went static
Access the static function with UNITTEST as designed.

Follow-up to 73c2b4b435

Closes #21788
2026-05-28 00:13:24 +02:00
Viktor Szakats
59320082b0
tidy-up: apply clang-format fixes
To lib, vtls/vauth, vtls/vquic, lib/vtls.

Also:
- unit3400: drop redundant `(void)arg`.
  Follow-up to e78b1b3ecc #21153
- fix comment typos.

Closes #21786
2026-05-28 00:05:47 +02:00
Aritra Basu
e78b1b3ecc
HTTP/3: add proxy CONNECT and MASQUE CONNECT-UDP support (ngtcp2 QUIC)
This patch adds two major proxy capabilities to curl (ngtcp2 QUIC):
- HTTP/3 Proxy CONNECT: Tunnel HTTP/1.1 or HTTP/2 traffic through an
  HTTPS proxy that speaks HTTP/3 (QUIC) using the standard CONNECT
  method over an HTTP/3 connection.
- MASQUE CONNECT-UDP: Tunnel HTTP/3 (QUIC) traffic through an HTTP
  proxy (speaking HTTP/1.1, HTTP/2, or HTTP/3) using the extended
  CONNECT method with the CONNECT-UDP protocol (RFC9297 & RFC9298).

Public API additions:
- `CURLPROXY_HTTPS3`: new proxy type constant for HTTP/3 proxy
- `--proxy-http3`: new CLI flag to negotiate HTTP/3 with HTTPS proxy

The implementation adds two new filters:
- `H3-PROXY` - enables negotiating HTTP/3 (QUIC) to the proxy and
  running CONNECT/CONNECT-UDP through that proxy transport.
- `CAPSULE` - dedicated filter inserted between QUIC transport and
  HTTP-PROXY to handle datagram capsule encapsulation/decapsulation.

Here is how the curl filter chaining looks in different scenarios:
- HTTP/3 Proxy CONNECT (tunneling TCP protocols over QUIC proxy):
  conn -> HTTP/1.1 or HTTP/2  -> SSL -> HTTP-PROXY ->
                                 H3-PROXY -> HAPPY-EYEBALLS -> UDP
- MASQUE CONNECT-UDP (tunneling QUIC over any proxy):
  conn -> HTTP/3 -> CAPSULE -> HTTP-PROXY -> H3-PROXY ->
                               HAPPY-EYEBALLS -> UDP
  conn -> HTTP/3 -> CAPSULE -> HTTP-PROXY -> H1-PROXY or H2-PROXY ->
                               SSL -> HAPPY-EYEBALLS -> TCP

- Both features currently require the ngtcp2 QUIC backend.
- Both features are experimental (disabled by default). Enable with
  `--enable-proxy-http3`(autotools) or `-DUSE_PROXY_HTTP3=ON`(CMake).

Tests:
- tests/unit/unit3400.c: Unit tests for capsule protocol encode/decode
- tests/http/test_60_h3_proxy.py: Comprehensive pytest integration suite
- tests/http/testenv/h2o.py: Managing h2o instances with HTTP/1.1, HTTP/2,
  and HTTP/3 (QUIC) listeners, proxy.connect and proxy.connect-udp enabled.

References:
  RFC 9297 - HTTP Datagrams and the Capsule Protocol
  RFC 9298 - Proxying UDP in HTTP
  RFC 9000 §16 — Variable-Length Integer Encoding

Signed-off-by: Aritra Basu <aritrbas+gh@cisco.com>

Closes #21153
2026-05-27 08:49:53 +02:00
Viktor Szakats
bb5500a752
units: tidy up begin/end blocks
- use `UNITTEST_BEGIN_SIMPLE`/`UNITTEST_END_SIMPLE` where missing.
- drop redundant `(void)arg;` where using `UNITTEST_BEGIN*`.
- unit1636: drop redundant block after `UNITTEST_BEGIN*`.
- unit1609: fix typo in comment.
- unit1627: merge to `if`s.

Closes #21715
2026-05-21 17:28:38 +02:00
Viktor Szakats
bcd0497c81
tidy-up: use curlx_safefree()
Closes #21700
2026-05-21 01:31:03 +02:00
Viktor Szakats
1c3289c85e
unit3303, unit3304: tidy-ups
- use `curlx_safefree()`.
- drop redundant blocks.

Follow-up to 7541ae569d #21667

Closes #21684
2026-05-20 00:48:54 +02:00
Joshua Rogers
7541ae569d
tls: fix incomplete mTLS config in conn reuse and session cache
cert_type, key, key_type, key_passwd and key_blob lived in
ssl_config_data but not in ssl_primary_config, so they were invisible to
match_ssl_primary_config() and to the TLS session cache peer key.

Two easy handles sharing a connection pool could reuse each other's
authenticated connections when they differed only on SSLKEY, SSLKEYTYPE,
KEYPASSWD, SSLCERTTYPE or SSLKEYBLOB. The second handle would silently
inherit the first handle's authenticated identity.

Promote all five fields into ssl_primary_config so the conn-reuse
predicate and session cache key cover the complete client credential
set. Also replace the fixed ":CCERT" session cache marker with the
actual clientcert path so sessions are not shared across different
client certificates.

Verified by test 3303 and 3304

Reported-By: Joshua Rogers (AISLE Research)
Closes #21667
2026-05-20 00:02:33 +02:00
Viktor Szakats
000de81fb1
tidy-up: rename more CURLcode variables to result
Follow-up to 885b553545 #21348

Closes #21676
2026-05-19 16:55:45 +02:00
Viktor Szakats
a7bfbc09d4
unit1304: use enum type and values, rename result to res
Ref: #21646

Closes #21673
2026-05-19 16:55:45 +02:00
Stefan Eissing
4ae1d7cc26
netrc: scanner refactor
Refactor the netrc scanner. Add test case for checking that the last
matched machine with unmatched login does not return the password as
success (unit1304).

Closes #21624
2026-05-18 15:18:09 +02:00
Viktor Szakats
614b94eecc
tidy-up: miscellaneous
- avoid "will" in builds scripts, scripts folder, curl_easy_ssls_export.md,
  and few other files.
- badwords: add "initialise", "nul terminated", "thread safety" and
  variations.
- prefer "null-terminat", where missing (two places).
- fix "null-terminat*" missing dash.
- hostip: merge two `#if` blocks.
- tool_doswin: fix comment
  Spotted by GitHub Code Quality
  Follow-up to 9a2663322c #17572
- fix stray spaces and newlines.

Closes #21638
2026-05-16 01:56:17 +02:00
Viktor Szakats
47f411c6d8
GHA: enable -Wunused-macros in clang-tidy jobs
Also fix fallouts found.

Windows clang-tidy CI job is a little pickier than I'd prefer due to the
`_CURL_TESTS_CONCAT=ON` option used there, and all macros considered
local, thus checked by the compiler. Upside: it revealed macro usage
dynamics in tests. If too annoying, `first.h` may be opted-out from the
concat logic. Some macros may also be deleted instead of `#if 0`-ing.

Follow-up to e0e56e9ae4 #21550
Follow-up to 5fa5cb3825 #20593

Closes #21554
2026-05-16 01:17:41 +02:00