Disable -Wdeprecated-non-prototype in the back branches.

There doesn't seem to be any good ABI-preserving way to silence
clang 15's -Wdeprecated-non-prototype warnings about our tree-walk
APIs.  While we've fixed it properly in HEAD, the only way to not
see hundreds of these in the back branches is to disable the
warnings.  We're not going to do anything about them, so we might
as well disable them.

I noticed that we also get some of these warnings about fmgr.c's
support for V0 function call convention, in branches before v10
where we removed that.  That's another area we aren't going to
change, so turning off the warning seems fine for that too.

Per project policy, this is a candidate for back-patching into
out-of-support branches: it suppresses annoying compiler warnings
but changes no behavior.  Hence, back-patch all the way to 9.2.

Discussion: https://postgr.es/m/CA+hUKGKpHPDTv67Y+s6yiC8KH5OXeDg6a-twWo_xznKTcG0kSA@mail.gmail.com

diff --git a/configure b/configure
index 1b5d01d019c652a3261002bc3e9754edd93911b6..507d33c64e1c1ce769916fefa6ba9befcfd17aa4 100755 (executable)
--- a/configure
+++ b/configure
@@ -5874,6 +5874,51 @@ fi
   if test -n "$NOT_THE_CFLAGS"; then
     CFLAGS="$CFLAGS -Wno-compound-token-split-by-macro"
   fi
+  # Similarly remove clang 15+'s deprecated-non-prototype, as it warns about
+  # tree-walking APIs that we can't reasonably change in the back branches.
+  NOT_THE_CFLAGS=""
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CC} supports -Wdeprecated-non-prototype, for NOT_THE_CFLAGS" >&5
+$as_echo_n "checking whether ${CC} supports -Wdeprecated-non-prototype, for NOT_THE_CFLAGS... " >&6; }
+if ${pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  pgac_save_CFLAGS=$CFLAGS
+pgac_save_CC=$CC
+CC=${CC}
+CFLAGS="${NOT_THE_CFLAGS} -Wdeprecated-non-prototype"
+ac_save_c_werror_flag=$ac_c_werror_flag
+ac_c_werror_flag=yes
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype=yes
+else
+  pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+ac_c_werror_flag=$ac_save_c_werror_flag
+CFLAGS="$pgac_save_CFLAGS"
+CC="$pgac_save_CC"
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype" >&5
+$as_echo "$pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype" >&6; }
+if test x"$pgac_cv_prog_CC_cflags__Wdeprecated_non_prototype" = x"yes"; then
+  NOT_THE_CFLAGS="${NOT_THE_CFLAGS} -Wdeprecated-non-prototype"
+fi
+
+
+  if test -n "$NOT_THE_CFLAGS"; then
+    CFLAGS="$CFLAGS -Wno-deprecated-non-prototype"
+  fi
   # Similarly disable useless truncation warnings from gcc 8+
   NOT_THE_CFLAGS=""
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CC} supports -Wformat-truncation, for NOT_THE_CFLAGS" >&5
@@ -6788,6 +6833,48 @@ fi
     BITCODE_CFLAGS="$BITCODE_CFLAGS -Wno-compound-token-split-by-macro"
   fi
   NOT_THE_CFLAGS=""
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CLANG} supports -Wdeprecated-non-prototype, for NOT_THE_CFLAGS" >&5
+$as_echo_n "checking whether ${CLANG} supports -Wdeprecated-non-prototype, for NOT_THE_CFLAGS... " >&6; }
+if ${pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  pgac_save_CFLAGS=$CFLAGS
+pgac_save_CC=$CC
+CC=${CLANG}
+CFLAGS="${NOT_THE_CFLAGS} -Wdeprecated-non-prototype"
+ac_save_c_werror_flag=$ac_c_werror_flag
+ac_c_werror_flag=yes
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype=yes
+else
+  pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+ac_c_werror_flag=$ac_save_c_werror_flag
+CFLAGS="$pgac_save_CFLAGS"
+CC="$pgac_save_CC"
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype" >&5
+$as_echo "$pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype" >&6; }
+if test x"$pgac_cv_prog_CLANG_cflags__Wdeprecated_non_prototype" = x"yes"; then
+  NOT_THE_CFLAGS="${NOT_THE_CFLAGS} -Wdeprecated-non-prototype"
+fi
+
+  if test -n "$NOT_THE_CFLAGS"; then
+    BITCODE_CFLAGS="$BITCODE_CFLAGS -Wno-deprecated-non-prototype"
+  fi
+  NOT_THE_CFLAGS=""
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${CLANG} supports -Wformat-truncation, for NOT_THE_CFLAGS" >&5
 $as_echo_n "checking whether ${CLANG} supports -Wformat-truncation, for NOT_THE_CFLAGS... " >&6; }
 if ${pgac_cv_prog_CLANG_cflags__Wformat_truncation+:} false; then :

diff --git a/configure.in b/configure.in
index 55df35b595eeb4c97e9fe4458c06477f3d35af0b..6ff7e92f14959db9957ad56a7a2912217fc440a1 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -516,6 +516,13 @@ if test "$GCC" = yes -a "$ICC" = no; then
   if test -n "$NOT_THE_CFLAGS"; then
     CFLAGS="$CFLAGS -Wno-compound-token-split-by-macro"
   fi
+  # Similarly remove clang 15+'s deprecated-non-prototype, as it warns about
+  # tree-walking APIs that we can't reasonably change in the back branches.
+  NOT_THE_CFLAGS=""
+  PGAC_PROG_CC_VAR_OPT(NOT_THE_CFLAGS, [-Wdeprecated-non-prototype])
+  if test -n "$NOT_THE_CFLAGS"; then
+    CFLAGS="$CFLAGS -Wno-deprecated-non-prototype"
+  fi
   # Similarly disable useless truncation warnings from gcc 8+
   NOT_THE_CFLAGS=""
   PGAC_PROG_CC_VAR_OPT(NOT_THE_CFLAGS, [-Wformat-truncation])
@@ -577,6 +584,11 @@ if test "$with_llvm" = yes ; then
     BITCODE_CFLAGS="$BITCODE_CFLAGS -Wno-compound-token-split-by-macro"
   fi
   NOT_THE_CFLAGS=""
+  PGAC_PROG_VARCC_VARFLAGS_OPT(CLANG, NOT_THE_CFLAGS, [-Wdeprecated-non-prototype])
+  if test -n "$NOT_THE_CFLAGS"; then
+    BITCODE_CFLAGS="$BITCODE_CFLAGS -Wno-deprecated-non-prototype"
+  fi
+  NOT_THE_CFLAGS=""
   PGAC_PROG_VARCC_VARFLAGS_OPT(CLANG, NOT_THE_CFLAGS, [-Wformat-truncation])
   if test -n "$NOT_THE_CFLAGS"; then
     BITCODE_CFLAGS="$BITCODE_CFLAGS -Wno-format-truncation"