This patch is really not necessary from a functional point of view. It
is only necessary if we want to silence a compiler warning.

Tested on `gcc (GCC) 13.1.1 20230511 (Red Hat 13.1.1-2)`.

After silencing this warning, all I am left with (given my build
configuration) is:

[1667/2280] Compiling C object src/pl/plpgsql/src/plpgsql.so.p/pl_exec.c.o
In file included from ../src/include/access/htup_details.h:22,
                 from ../src/pl/plpgsql/src/pl_exec.c:21:
In function ‘assign_simple_var’,
    inlined from ‘exec_set_found’ at ../src/pl/plpgsql/src/pl_exec.c:8349:2:
../src/include/varatt.h:230:36: warning: array subscript 0 is outside array 
bounds of ‘char[0]’ [-Warray-bounds=]
  230 |         (((varattrib_1b_e *) (PTR))->va_tag)
      |                                    ^
../src/include/varatt.h:94:12: note: in definition of macro ‘VARTAG_IS_EXPANDED’
   94 |         (((tag) & ~1) == VARTAG_EXPANDED_RO)
      |            ^~~
../src/include/varatt.h:284:57: note: in expansion of macro ‘VARTAG_1B_E’
  284 | #define VARTAG_EXTERNAL(PTR)                            VARTAG_1B_E(PTR)
      |                                                         ^~~~~~~~~~~
../src/include/varatt.h:301:57: note: in expansion of macro ‘VARTAG_EXTERNAL’
  301 |         (VARATT_IS_EXTERNAL(PTR) && 
!VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR)))
      |                                                         ^~~~~~~~~~~~~~~
../src/pl/plpgsql/src/pl_exec.c:8537:17: note: in expansion of macro 
‘VARATT_IS_EXTERNAL_NON_EXPANDED’
 8537 |                 
VARATT_IS_EXTERNAL_NON_EXPANDED(DatumGetPointer(newvalue)))
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

>From my perspective, this warning definitely seems like a false
positive, but I don't know the code well-enough to say that for certain.

-- 
Tristan Partin
Neon (https://neon.tech)
From 0daab1d0231668da4ac701bd240fc1da5fbcd5bb Mon Sep 17 00:00:00 2001
From: Tristan Partin <tris...@neon.tech>
Date: Wed, 7 Jun 2023 09:21:59 -0500
Subject: [PATCH v1] Fix last remaining uninitialized memory warnings

gcc fails to properly analyze the code due to the loop stop condition
including `l != NULL`. Let's just help it out.
---
 src/bin/pgbench/pgbench.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 1d1670d4c2..536f1721ff 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -2247,7 +2247,7 @@ evalStandardFunc(CState *st,
 {
 	/* evaluate all function arguments */
 	int			nargs = 0;
-	PgBenchValue vargs[MAX_FARGS];
+	PgBenchValue vargs[MAX_FARGS] = { 0 };
 	PgBenchExprLink *l = args;
 	bool		has_null = false;
 
-- 
-- 
Tristan Partin
Neon (https://neon.tech)

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