pgsql: Silence -fsanitize=function where we cast function pointers on p

Silence -fsanitize=function where we cast function pointers on purpose

In clang, -fsanitize=undefined includes -fsanitize=function, which
reports every call made through a function pointer whose type does not
exactly match the called function, so it fires all over the place on
expression tree walkers and mutators, as well as a few other places.
So -fsanitize=undefined hasn't been working cleanly under clang for a
while. (Before clang 17, it only applied to C++.)

This is the same issue that caused us to use
-Wno-cast-function-type-strict with clang. That warning applies at
the place where the mismatching function pointer is passed, so there
are potentially hundreds of sites. Therefore, a global disabling is
appropriate. The sanitizer, on the other hand, triggers where the
function is called, which are only about two dozen places, so it seems
possible to silence these checks individually and still main the check
for accidental violations elsewhere.

Add pg_attribute_no_sanitize_function() and place it on the functions
that make such calls.

Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/2db401d9-ef16-430e-a42c-34477006a49f%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3ff475ac12ec8d8d07cf3fd86144659285a59d83

Modified Files
--------------
contrib/pgcrypto/pgcrypto.c | 1 +
src/backend/access/heap/heapam.c | 1 +
src/backend/nodes/nodeFuncs.c | 12 ++++++++++++
src/backend/parser/analyze.c | 1 +
src/backend/utils/hash/dynahash.c | 2 ++
src/backend/utils/mmgr/mcxt.c | 1 +
src/include/c.h | 16 ++++++++++++++++
src/include/executor/execScan.h | 1 +
src/include/lib/sort_template.h | 2 ++
src/pl/plpgsql/src/pl_funcs.c | 1 +
10 files changed, 38 insertions(+)