python / python/cpython

Compiling static library with `-fPIC` throws error

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build type-bug
Dominant language
Python
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Description

Bug report

I'm compiling python as a static library to embed in my c++ shared library, and -fPIC is necessary to get it working!

compilation command: CFLAGS=-fPIC ./configure --enable-shared=no --enable-optimizations

the following error happens:

Objects/typeobject.c: In function ‘inherit_special’:
Objects/typeobject.c:5777:1: error: the control flow of function ‘inherit_special’ does not match its profile data (counter ‘arcs’) [-Werror=coverage-mismatch]
 5777 | inherit_special(PyTypeObject *type, PyTypeObject *base)
      | ^~~~~~~~~~~~~~~
Objects/typeobject.c:5777:1: error: the control flow of function ‘inherit_special’ does not match its profile data (counter ‘time_profiler’) [-Werror=coverage-mismatch]
Objects/typeobject.c: In function ‘object_set_class’:
Objects/typeobject.c:4774:1: error: the control flow of function ‘object_set_class’ does not match its profile data (counter ‘arcs’) [-Werror=coverage-mismatch]
 4774 | object_set_class(PyObject *self, PyObject *value, void *closure)
      | ^~~~~~~~~~~~~~~~
Objects/typeobject.c:4774:1: error: the control flow of function ‘object_set_class’ does not match its profile data (counter ‘time_profiler’) [-Werror=coverage-mismatch]
Objects/obmalloc.c:1449:1: warning: ‘always_inline’ function might not be inlinable [-Wattributes]
 1449 | arena_map_get(block *p, int create)
      | ^~~~~~~~~~~~~

if I remove the -fPIC it compiles fine!
edit: Just tried removing --enable-optimizations and it worked, but I think it should work with optimizations?

Your environment

  • CPython versions tested on: branch 3.11
  • Operating system and architecture: Manjaro Linux x64

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First steps

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Research direction

Reproduce the issue with CFLAGS=-fPIC ./configure --enable-shared=no --enable-optimizations on CPython 3.11, then compare it with the successful build without -fPIC or --enable-optimizations. Start with the reported failures in Objects/typeobject.c and warning in Objects/obmalloc.c; done means the optimized static build completes with -fPIC.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp, python
Domain
build-system, compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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