Add test for build of libpqxx with enabled exceptions

This resolves FTBFS with libpqxx 3.x

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

kexi/kexidb/drivers/configure.in.in

@@ -248,14 +248,31 @@ if test "$compile_pgsql_plugin" = "yes"; then
   AC_LANG_SAVE
   AC_LANG_CPLUSPLUS
   SAVED_CXXFLAGS="$CXXFLAGS"
-  for CXX_STD_TEST in "" 11 14 17; do
-    CXXFLAGS="$SAVED_CXXFLAGS"
-    if test "x$CXX_STD_TEST" = "x"; then
-      AC_MSG_CHECKING([PostgreSQL build with default C++ standard])
-    else
+  AC_MSG_CHECKING([PostgreSQL build with default flags])
+  PQXX_CXXFLAGS=""
+  CXXFLAGS="$SAVED_CXXFLAGS $PQXX_CXXFLAGS"
+  AC_TRY_COMPILE([
+      #include <$PQXX_INCDIR/pqxx/pqxx>
+    ],[ ],
+    pqxx_flags=yes,
+    pqxx_flags=no
+  )
+  if test "x$pqxx_flags" = "xno"; then
+    AC_MSG_RESULT(no)
+    AC_MSG_CHECKING([PostgreSQL build with enabled exceptions])
+    PQXX_CXXFLAGS+=" $USE_EXCEPTIONS"
+    CXXFLAGS="$SAVED_CXXFLAGS $PQXX_CXXFLAGS"
+    AC_TRY_COMPILE([
+        #include <$PQXX_INCDIR/pqxx/pqxx>
+      ],[ ],
+      pqxx_exceptions=yes,
+      pqxx_exceptions=no
+    )
+    if test "x$pqxx_exceptions" = "xno"; then
+      AC_MSG_RESULT(no)
+      for CXX_STD_TEST in 11 14 17; do
         AC_MSG_CHECKING([PostgreSQL build with C++$CXX_STD_TEST])
-      CXXFLAGS=-std=c++$CXX_STD_TEST
-    fi
+        CXXFLAGS="$SAVED_CXXFLAGS $PQXX_CXXFLAGS -std=c++$CXX_STD_TEST"
         AC_TRY_COMPILE([
             #include <$PQXX_INCDIR/pqxx/pqxx>
           ],[ ],
@@ -263,16 +280,24 @@ if test "$compile_pgsql_plugin" = "yes"; then
           pqxx_cxx_std=no
         )
         if test "x$pqxx_cxx_std" = "xyes"; then
-      PQXX_CXXFLAGS=$CXXFLAGS
+          AC_MSG_RESULT(yes)
           compile_pgsql_plugin="yes"
+          PQXX_CXXFLAGS+=" -std=c++$CXX_STD_TEST"
           AC_SUBST(PQXX_CXXFLAGS)
-      AC_MSG_RESULT(yes)
           break
         else
-      compile_pgsql_plugin="no"
           AC_MSG_RESULT(no)
+          compile_pgsql_plugin="no"
         fi
       done
+    else
+      AC_MSG_RESULT(yes)
+      AC_SUBST(PQXX_CXXFLAGS)
+    fi
+  else
+    AC_MSG_RESULT(yes)
+    AC_SUBST(PQXX_CXXFLAGS)
+  fi
   CXXFLAGS="$SAVED_CXXFLAGS"
   AC_LANG_RESTORE
 fi