Before this patch curl used the C preprocessor to override standard
memory allocation symbols: malloc, calloc, strdup, realloc, free.
The goal of these is to replace them with curl's debug wrappers in
`CURLDEBUG` builds, another was to replace them with the wrappers
calling user-defined allocators in libcurl. This solution needed a bunch
of workarounds to avoid breaking external headers: it relied on include
order to do the overriding last. For "unity" builds it needed to reset
overrides before external includes. Also in test apps, which are always
built as single source files. It also needed the `(symbol)` trick
to avoid overrides in some places. This would still not fix cases where
the standard symbols were macros. It was also fragile and difficult
to figure out which was the actual function behind an alloc or free call
in a specific piece of code. This in turn caused bugs where the wrong
allocator was accidentally called.
To avoid these problems, this patch replaces this solution with
`curlx_`-prefixed allocator macros, and mapping them _once_ to either
the libcurl wrappers, the debug wrappers or the standard ones, matching
the rest of the code in libtests.
This concludes the long journey to avoid redefining standard functions
in the curl codebase.
Note: I did not update `packages/OS400/*.c` sources. They did not
`#include` `curl_setup.h`, `curl_memory.h` or `memdebug.h`, meaning
the overrides were never applied to them. This may or may not have been
correct. For now I suppressed the direct use of standard allocators
via a local `.checksrc`. Probably they (except for `curlcl.c`) should be
updated to include `curl_setup.h` and use the `curlx_` macros.
This patch changes mappings in two places:
- `lib/curl_threads.c` in libtests: Before this patch it mapped to
libcurl allocators. After, it maps to standard allocators, like
the rest of libtests code.
- `units`: before this patch it mapped to standard allocators. After, it
maps to libcurl allocators.
Also:
- drop all position-dependent `curl_memory.h` and `memdebug.h` includes,
and delete the now unnecessary headers.
- rename `Curl_tcsdup` macro to `curlx_tcsdup` and define like the other
allocators.
- map `curlx_strdup()` to `_strdup()` on Windows (was: `strdup()`).
To fix warnings silenced via `_CRT_NONSTDC_NO_DEPRECATE`.
- multibyte: map `curlx_convert_*()` to `_strdup()` on Windows
(was: `strdup()`).
- src: do not reuse the `strdup` name for the local replacement.
- lib509: call `_strdup()` on Windows (was: `strdup()`).
- test1132: delete test obsoleted by this patch.
- CHECKSRC.md: update text for `SNPRINTF`.
- checksrc: ban standard allocator symbols.
Follow-up to b12da22db1#18866
Follow-up to db98daab05#18844
Follow-up to 4deea9396b#18814
Follow-up to 9678ff5b1b#18776
Follow-up to 10bac43b87#18774
Follow-up to 20142f5d06#18634
Follow-up to bf7375ecc5#18503
Follow-up to 9863599d69#18502
Follow-up to 3bb5e58c10#17827Closes#19626
Windows CE support was limited to successful builds with ming32ce
(a toolchain that hasn't seen an update since 2009, using an ancient gcc
version and "old mingw"-style SDK headers, that curl deprecated earlier).
Builds with MSVC were broken for a long time. mingw32ce builds were never
actually tested and runtime and unlikely to work due to missing stubs.
Windows CE toolchains also miss to comply with C89. Paired with lack of
demand and support for the platform, curl deprecated it earlier.
This patch removes support from the codebase to ease maintaining Windows
codepaths.
Follow-up to f98c0ba834#17924
Follow-up to 8491e6574c#17379
Follow-up to 2a292c3984#15975Closes#17927
- GHA/checkdocs: rename `spellcheck` job to `pyspelling` to say
the exact tool used.
- GHA/checkdocs: restore a comment.
- GHA/linux: add `-B .` to a cmake configure to avoid warning, and
future breakage.
- autotools: use correct casing for `Schannel`.
- doh: update RFC URL.
- drop redundant parenthesis.
- fix indentation, whitespace.
Closes#18756
`-Weverything` is not enabled by curl, and not recommended by LLVM,
because it may enable experimental options, and will result in new
fallouts after toolchain upgrades. This patch aims to fix/silence as much
as possible as found with llvm/clang 21.1.0. It also permanently enables
warnings that were fixed in source and deemed manageable in the future.
`-Wformat` warnings are addressed separately via #18343.
Fix/silence warnings in the source:
- typecheck-gcc.h: fix `-Wreserved-identifier`.
- lib: silence `-Wcast-function-type-strict`.
For llvm 16+ or Apple clang 16+.
- asyn-ares: limit `HAPPY_EYEBALLS_DNS_TIMEOUT` to old c-ares versions.
- curl_trc: fix `-Wc++-hidden-decl`.
- doh: fix `-Wc++-keyword`.
- ftp: fix `-Wreserved-identifier`.
- ldap: fix `-Wreserved-identifier`.
- mqtt: comment unused macro to avoid warning.
- multi_ev: drop unused macros to avoid warnings.
- setopt: fix useless `break;` after `return;`.
- gtls, mbedtls, rustls: silence `-Wconditional-uninitialized`.
- socks_sspi, schannel, x509asn1: fix `-Wimplicit-int-enum-cast`.
- x509asn1: fix `-Wc++-keyword`.
- openssl: scope `OSSL_UI_METHOD_CAST` to avoid unused macro warning.
- libssh2, wolfssl: drop unused macros.
- curl_ngtcp2, curl_quiche, httpsrr, urlapi: drop/limit unused macros.
- tool_getparam: fix useless `break;` after `return;` or `break;`.
Not normally enabled because it doesn't work with unity.
https://github.com/llvm/llvm-project/issues/71046
- tool_operate: fix `-Wc++-keyword`.
- curlinfo: fix a `-Wunsafe-buffer-usage`.
- tests: silence `-Wformat-non-iso`.
- lib557: fix `-Wreserved-identifier`.
- lib1565: silence `-Wconditional-uninitialized`.
Enable the above clang warnings permanently in picky mode:
- `-Wc++-hidden-decl`
- `-Wc++-keyword` (except for Windows, where it collides with `wchar_t`)
- `-Wcast-function-type-strict`
- `-Wcast-function-type`
- `-Wconditional-uninitialized`
- `-Wformat-non-iso` (except for clang-cl)
- `-Wreserved-identifier`
- `-Wtentative-definition-compat`
Silence problematic `-Weverything` warnings globally (in picky mode):
- `-Wused-but-marked-unused` (88000+ hits) and
`-Wdisabled-macro-expansion` (2600+ hits).
Triggered by `typecheck-gcc.h` when building with clang 14+.
Maybe there exists a way to fix within that header?
Ref: https://discourse.llvm.org/t/removing-wused-but-marked-unused/55310
- `-Wunsafe-buffer-usage`. clang 16+. 7000+ hits.
May be useful in theory, but such high volume of hits makes it
impractical to review and possibly address. Meant for C++.
Ref: https://clang.llvm.org/docs/SafeBuffers.html
Ref: https://stackoverflow.com/questions/77017567/how-to-fix-code-to-avoid-warning-wunsafe-buffer-usage
Ref: https://discourse.llvm.org/t/rfc-c-buffer-hardening/65734
Ref: https://github.com/llvm/llvm-project/pull/111624
- `-Wimplicit-void-ptr-cast`. clang 21+. 1700+ hits.
C++ warning, deemed pure noise.
Ref: https://github.com/curl/curl/issues/18470#issuecomment-3253506266
- `-Wswitch-default` (180+ hits), `-Wswitch-enum` (190+ hits),
`-Wcovered-switch-default` (20+ hits).
Next to impossible to fix cleanly, esp. when the covered `case`
branches depend on compile-time options.
- `-Wdocumentation-unknown-command` (8+ hits).
Triggered in a few sources. Seems arbitrary and bogus.
- `-Wpadded` (550+ hits).
- `-Wc++-keyword` on Windows, where it collides with `wchar_t`.
(100+ hits)
Ref: https://github.com/llvm/llvm-project/issues/155988
- `-Wreserved-macro-identifier`. clang 13+. 5+ hits.
Sometimes it's necessary to set external macros that use
the reserved namespace. E.g. `_CRT_NONSTDC_NO_DEPRECATE`,
`__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__`, `__NO_NET_API`,
possibly `_REENTRANT`, and more.
It's not worth trying to silence them individually.
- `-Wnonportable-system-include-path` with `clang-cl`.
It'd be broken by doing what the warning suggests.
- `-Wformat-non-iso` for clang-cl.
CMake `PICKY_COMPILER=ON` (the default) or `./configure`
`--enable-warnings` (not the default) is required to enable these
silencing rules.
Also:
- autotools, cmake: fix Apple clang and mainline llvm version translations.
Ref: https://en.wikipedia.org/wiki/Xcode#Toolchain_versions
- autotools, cmake: enable `-Warray-compare` for clang 20+.
Follow-up to 4b7accda5a#17196
- cmake: fix to enable `-Wmissing-variable-declarations` at an earlier
clang version.
- cmake: update internal logic to handle warning options with `+` in
them.
- cmake: fix internal logic to match the whole option when looking
into `CMAKE_C_FLAGS` for custom-disabled warnings.
Follow-up to b85cb8cb4e#18485Closes#18477
