Unable to `pip install multidict` with `gcc-14`

[psss]

Long story short

With the latest Fedora Rawhide which freshly contains gcc-14 I'm not able to install multidict.

Expected behaviour

Package successfully installed.

Actual behaviour

I see the following error:

gcc -fno-strict-overflow -Wsign-compare -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DNDEBUG -fexceptions -fcf-protection -fexceptions -fcf-protection -fexceptions -fcf-protection -fPIC -I/tmp/venv/include -I/usr/include/python3.12 -c multidict/_multidict.c -o build/temp.linux-x86_64-cpython-312/multidict/_multidict.o -O2 -std=c99 -Wall -Wsign-compare -Wconversion -fno-strict-aliasing -pedantic
multidict/_multidict.c: In function ‘multidict_getall’:
multidict/_multidict.c:458:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  458 |     static _PyArg_Parser _parser = {NULL, _keywords, "getall", 0};
      |                                     ^~~~
multidict/_multidict.c:458:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:458:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  458 |     static _PyArg_Parser _parser = {NULL, _keywords, "getall", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:458:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:458:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  458 |     static _PyArg_Parser _parser = {NULL, _keywords, "getall", 0};
      |                                                      ^~~~~~~~
multidict/_multidict.c:458:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_getone’:
multidict/_multidict.c:503:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  503 |     static _PyArg_Parser _parser = {NULL, _keywords, "getone", 0};
      |                                     ^~~~
multidict/_multidict.c:503:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:503:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  503 |     static _PyArg_Parser _parser = {NULL, _keywords, "getone", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:503:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:503:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  503 |     static _PyArg_Parser _parser = {NULL, _keywords, "getone", 0};
      |                                                      ^~~~~~~~
multidict/_multidict.c:503:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_get’:
multidict/_multidict.c:538:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  538 |     static _PyArg_Parser _parser = {NULL, _keywords, "get", 0};
      |                                     ^~~~
multidict/_multidict.c:538:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:538:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  538 |     static _PyArg_Parser _parser = {NULL, _keywords, "get", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:538:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:538:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  538 |     static _PyArg_Parser _parser = {NULL, _keywords, "get", 0};
      |                                                      ^~~~~
multidict/_multidict.c:538:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_tp_dealloc’:
multidict/_multidict.c:712:5: warning: ‘UsingDeprecatedTrashcanMacro’ is deprecated [-Wdeprecated-declarations]
  712 |     Py_TRASHCAN_SAFE_BEGIN(self);
      |     ^~~~~~~~~~~~~~~~~~~~~~
multidict/_multidict.c: In function ‘multidict_add’:
multidict/_multidict.c:780:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  780 |     static _PyArg_Parser _parser = {NULL, _keywords, "add", 0};
      |                                     ^~~~
multidict/_multidict.c:780:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:780:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  780 |     static _PyArg_Parser _parser = {NULL, _keywords, "add", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:780:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:780:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  780 |     static _PyArg_Parser _parser = {NULL, _keywords, "add", 0};
      |                                                      ^~~~~
multidict/_multidict.c:780:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_setdefault’:
multidict/_multidict.c:839:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  839 |     static _PyArg_Parser _parser = {NULL, _keywords, "setdefault", 0};
      |                                     ^~~~
multidict/_multidict.c:839:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:839:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  839 |     static _PyArg_Parser _parser = {NULL, _keywords, "setdefault", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:839:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:839:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  839 |     static _PyArg_Parser _parser = {NULL, _keywords, "setdefault", 0};
      |                                                      ^~~~~~~~~~~~
multidict/_multidict.c:839:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_popone’:
multidict/_multidict.c:875:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  875 |     static _PyArg_Parser _parser = {NULL, _keywords, "popone", 0};
      |                                     ^~~~
multidict/_multidict.c:875:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:875:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  875 |     static _PyArg_Parser _parser = {NULL, _keywords, "popone", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:875:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:875:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  875 |     static _PyArg_Parser _parser = {NULL, _keywords, "popone", 0};
      |                                                      ^~~~~~~~
multidict/_multidict.c:875:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_pop’:
multidict/_multidict.c:922:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  922 |     static _PyArg_Parser _parser = {NULL, _keywords, "pop", 0};
      |                                     ^~~~
multidict/_multidict.c:922:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:922:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  922 |     static _PyArg_Parser _parser = {NULL, _keywords, "pop", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:922:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:922:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  922 |     static _PyArg_Parser _parser = {NULL, _keywords, "pop", 0};
      |                                                      ^~~~~
multidict/_multidict.c:922:54: note: (near initialization for ‘_parser.keywords’)
multidict/_multidict.c: In function ‘multidict_popall’:
multidict/_multidict.c:970:37: error: initialization of ‘int’ from ‘void *’ makes integer from pointer without a cast [-Wint-conversion]
  970 |     static _PyArg_Parser _parser = {NULL, _keywords, "popall", 0};
      |                                     ^~~~
multidict/_multidict.c:970:37: note: (near initialization for ‘_parser.initialized’)
multidict/_multidict.c:970:43: error: initialization of ‘const char *’ from incompatible pointer type ‘const char * const*’ [-Wincompatible-pointer-types]
  970 |     static _PyArg_Parser _parser = {NULL, _keywords, "popall", 0};
      |                                           ^~~~~~~~~
multidict/_multidict.c:970:43: note: (near initialization for ‘_parser.format’)
multidict/_multidict.c:970:54: error: initialization of ‘const char * const*’ from incompatible pointer type ‘char *’ [-Wincompatible-pointer-types]
  970 |     static _PyArg_Parser _parser = {NULL, _keywords, "popall", 0};
      |                                                      ^~~~~~~~
multidict/_multidict.c:970:54: note: (near initialization for ‘_parser.keywords’)
error: command '/usr/bin/gcc' failed with exit code 1

Steps to reproduce

Install the latest rawhide.

python3 -m venv /tmp/venv
/tmp/venv/bin/pip install multidict

Your environment

Fedora-Cloud-Base-Rawhide-20240117.n.0.x86_64.qcow2
gcc-14.0.1-0.1.fc40.x86_64

[webknjaz]

Thanks for the report! Could you confirm this against master?

I don't know what GCC version is used in CI but it doesn't error out.

P.S. There's another issue tracking the release of wheels for py312.

[psss]

Yes, I'm seeing the same error with 68b080e.

[hroncok]

_parser.initialized is an int. I suppose replacing all the NULLs with zeros will get rid of the -Wint-conversion one

[hroncok]

I would also guess that passing _keywords as the second value seems bogus, because the second value is format, not keywords...

Oh. Since Python 3.12, the first int value was added. See python/cpython@6f6a4e6 -- hence the entire order of values here needs to be shifted.

[hroncok]

Perhaps initializing like this makes more sense?

multidict/multidict/_multidict.c

Lines 865 to 869 in 68b080e

	static _PyArg_Parser _parser = {
	.keywords = _keywords,
	.fname = "add",
	.kwtuple = NULL,
	};

[hroncok]

The bit I don't understand is this: How did this ever work on Python 3.12 in the first place?

[charles-dyfis-net]

This isn't limited to gcc-14; the same occurs building against Python 2.13 3.12 with clang 16.0.6 on MacOS.

[charles-dyfis-net]

One way to fix this, albeit with a performance penalty, is to extend the PR dropping use of METH_FASTCALL from Python 3.13 to drop it from 3.12 as well; I have a branch doing this as charles-dyfis-net/multidict@ad11386

[webknjaz]

Feel free to submit a PR, with maybe some tests that would show that it works as expected?
I didn't write that original code, so I don't fully understand all the inner workings. Hopefully, the partial revert I made @ #909 is correct. At least the CI passes (and it made the 3.13 jobs green).

Any idea why that is? Does the older GCC compile things differently? After all, the wheels being tested are built in the manylinux images with a GCC version that's hardly modern. The tests (except for the 3.13 job) don't recompile the project but install those wheels for testing.