Fix -Wcast-function-type warnings Three groups of issues needed to be addressed:
load_external_function() and related functions returned PGFunction, even though not necessarily all callers are looking for a function of type PGFunction. Since these functions are really just wrappers around dlsym(), change to return void * just like dlsym(). In dynahash.c, we are using strlcpy() where a function with a signature like memcpy() is expected. This should be safe, as the new comment there explains, but the cast needs to be augmented to avoid the warning. In PL/Python, methods all need to be cast to PyCFunction, per Python API, but this now runs afoul of these warnings. (This issue also exists in core CPython.) To fix the second and third case, we add a new type pg_funcptr_t that is defined specifically so that gcc accepts it as a special function pointer that can be cast to any other function pointer without the warning. Also add -Wcast-function-type to the standard warning flags, subject to configure check. Reviewed-by: Tom Lane <t...@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/1e97628e-6447-b4fd-e230-d109cec2d584%402ndquadrant.com (cherry picked from commit de8feb1f3a23465b5737e8a8c160e8ca62f61339) Author: Peter Eisentraut <pe...@eisentraut.org> Author: Alexandra Wang <alexandra.wang....@gmail.com> Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/a5abacecb46358a7b771841e2ee0acbb1c353b79 Author: Peter Eisentraut <pe...@eisentraut.org> Modified Files -------------- configure | 91 +++++++++++++++++++++++++++++++++++++++ configure.in | 2 + src/backend/utils/fmgr/dfmgr.c | 14 +++--- src/backend/utils/hash/dynahash.c | 11 ++++- src/include/c.h | 7 +++ src/include/fmgr.h | 6 +-- src/pl/plpython/plpy_plpymodule.c | 14 +++--- 7 files changed, 127 insertions(+), 18 deletions(-)
