diff --git a/src/xkbcomp/action.c b/src/xkbcomp/action.c
index 5706626..ee09865 100644
--- a/src/xkbcomp/action.c
+++ b/src/xkbcomp/action.c
@@ -221,7 +221,7 @@ CheckLatchLockFlags(struct xkb_keymap *keymap, unsigned action,
                     unsigned field, ExprDef * value, unsigned *flags_inout)
 {
     unsigned tmp;
-    ExprResult result;
+    bool result;
 
     if (field == F_ClearLocks)
         tmp = XkbSA_ClearLocks;
@@ -229,12 +229,15 @@ CheckLatchLockFlags(struct xkb_keymap *keymap, unsigned action,
         tmp = XkbSA_LatchToLock;
     else
         return false;           /* WSGO! */
+
     if (!ExprResolveBoolean(keymap->ctx, value, &result))
         return ReportMismatch(keymap, action, field, "boolean");
-    if (result.uval)
+
+    if (result)
         *flags_inout |= tmp;
     else
         *flags_inout &= ~tmp;
+
     return true;
 }
 
@@ -453,13 +456,17 @@ HandleMovePtr(struct xkb_keymap *keymap, struct xkb_any_action *action,
         return true;
     }
     else if (field == F_Accel) {
-        if (!ExprResolveBoolean(keymap->ctx, value, &rtrn))
+        bool set;
+
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportMismatch(keymap, action->type, field, "boolean");
-        if (rtrn.uval)
+
+        if (set)
             act->flags &= ~XkbSA_NoAcceleration;
         else
             act->flags |= XkbSA_NoAcceleration;
     }
+
     return ReportIllegal(keymap, action->type, field);
 }
 
@@ -678,16 +685,22 @@ HandleSwitchScreen(struct xkb_keymap *keymap, struct xkb_any_action *action,
         return true;
     }
     else if (field == F_Same) {
-        if (array_ndx != NULL)
+        bool set;
+
+        if (array_ndx)
             return ReportActionNotArray(keymap, action->type, field);
-        if (!ExprResolveBoolean(keymap->ctx, value, &rtrn))
+
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportMismatch(keymap, action->type, field, "boolean");
-        if (rtrn.uval)
+
+        if (set)
             act->flags &= ~XkbSA_SwitchApplication;
         else
             act->flags |= XkbSA_SwitchApplication;
+
         return true;
     }
+
     return ReportIllegal(keymap, action->type, field);
 }
 
@@ -750,6 +763,7 @@ HandleActionMessage(struct xkb_keymap *keymap, struct xkb_any_action *action,
 {
     ExprResult rtrn;
     const char *str;
+    bool set;
     struct xkb_message_action *act;
 
     act = (struct xkb_message_action *) action;
@@ -766,14 +780,17 @@ HandleActionMessage(struct xkb_keymap *keymap, struct xkb_any_action *action,
         return true;
 
     case F_GenKeyEvent:
-        if (array_ndx != NULL)
+        if (array_ndx)
             return ReportActionNotArray(keymap, action->type, field);
-        if (!ExprResolveBoolean(keymap->ctx, value, &rtrn))
+
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportMismatch(keymap, action->type, field, "boolean");
-        if (rtrn.uval)
+
+        if (set)
             act->flags |= XkbSA_MessageGenKeyEvent;
         else
             act->flags &= ~XkbSA_MessageGenKeyEvent;
+
         return true;
 
     case F_Data:
diff --git a/src/xkbcomp/compat.c b/src/xkbcomp/compat.c
index 7fb5063..ea42f21 100644
--- a/src/xkbcomp/compat.c
+++ b/src/xkbcomp/compat.c
@@ -665,32 +665,36 @@ SetInterpField(CompatInfo *info, SymInterpInfo *si, const char *field,
             return ReportSIBadType(info, si, field, "virtual modifier");
     }
     else if (istreq(field, "repeat")) {
-        if (arrayNdx != NULL)
+        bool set;
+
+        if (arrayNdx)
             return ReportSINotArray(info, si, field);
-        ok = ExprResolveBoolean(keymap->ctx, value, &tmp);
-        if (ok) {
-            if (tmp.uval)
-                si->interp.flags |= XkbSI_AutoRepeat;
-            else
-                si->interp.flags &= ~XkbSI_AutoRepeat;
-            si->defined |= _SI_AutoRepeat;
-        }
-        else
+
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportSIBadType(info, si, field, "boolean");
+
+        if (set)
+            si->interp.flags |= XkbSI_AutoRepeat;
+        else
+            si->interp.flags &= ~XkbSI_AutoRepeat;
+
+        si->defined |= _SI_AutoRepeat;
     }
     else if (istreq(field, "locking")) {
-        if (arrayNdx != NULL)
+        bool set;
+
+        if (arrayNdx)
             return ReportSINotArray(info, si, field);
-        ok = ExprResolveBoolean(keymap->ctx, value, &tmp);
-        if (ok) {
-            if (tmp.uval)
-                si->interp.flags |= XkbSI_LockingKey;
-            else
-                si->interp.flags &= ~XkbSI_LockingKey;
-            si->defined |= _SI_LockingKey;
-        }
-        else
+
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportSIBadType(info, si, field, "boolean");
+
+        if (set)
+            si->interp.flags |= XkbSI_LockingKey;
+        else
+            si->interp.flags &= ~XkbSI_LockingKey;
+
+        si->defined |= _SI_LockingKey;
     }
     else if (istreq(field, "usemodmap") ||
              istreq(field, "usemodmapmods")) {
@@ -789,16 +793,19 @@ SetIndicatorMapField(CompatInfo *info, LEDInfo *led,
         led->defined |= _LED_Ctrls;
     }
     else if (istreq(field, "allowexplicit")) {
-        if (arrayNdx != NULL)
+        bool set;
+
+        if (arrayNdx)
             return ReportIndicatorNotArray(info, led, field);
 
-        if (!ExprResolveBoolean(keymap->ctx, value, &rtrn))
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportIndicatorBadType(info, led, field, "boolean");
 
-        if (rtrn.uval)
+        if (set)
             led->flags &= ~XkbIM_NoExplicit;
         else
             led->flags |= XkbIM_NoExplicit;
+
         led->defined |= _LED_Explicit;
     }
     else if (istreq(field, "whichmodstate") ||
@@ -828,16 +835,19 @@ SetIndicatorMapField(CompatInfo *info, LEDInfo *led,
              istreq(field, "leddriveskeyboard") ||
              istreq(field, "indicatordriveskbd") ||
              istreq(field, "indicatordriveskeyboard")) {
-        if (arrayNdx != NULL)
+        bool set;
+
+        if (arrayNdx)
             return ReportIndicatorNotArray(info, led, field);
 
-        if (!ExprResolveBoolean(keymap->ctx, value, &rtrn))
+        if (!ExprResolveBoolean(keymap->ctx, value, &set))
             return ReportIndicatorBadType(info, led, field, "boolean");
 
-        if (rtrn.uval)
+        if (set)
             led->flags |= XkbIM_LEDDrivesKB;
         else
             led->flags &= ~XkbIM_LEDDrivesKB;
+
         led->defined |= _LED_DrivesKbd;
     }
     else if (istreq(field, "index")) {
diff --git a/src/xkbcomp/expr.c b/src/xkbcomp/expr.c
index 150dce1..2d71ca7 100644
--- a/src/xkbcomp/expr.c
+++ b/src/xkbcomp/expr.c
@@ -214,11 +214,10 @@ LookupModMask(struct xkb_context *ctx, const void *priv, xkb_atom_t field,
     return ret;
 }
 
-int
-ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
-                   ExprResult *val_rtrn)
+bool
+ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr, bool *set_rtrn)
 {
-    int ok = 0;
+    bool ok = false;
     const char *ident;
 
     switch (expr->op) {
@@ -229,7 +228,7 @@ ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
                     exprValueTypeText(expr->value_type));
             return false;
         }
-        val_rtrn->ival = expr->value.ival;
+        *set_rtrn = !!expr->value.ival;
         return true;
 
     case EXPR_IDENT:
@@ -238,13 +237,13 @@ ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
             if (istreq(ident, "true") ||
                 istreq(ident, "yes") ||
                 istreq(ident, "on")) {
-                val_rtrn->uval = 1;
+                *set_rtrn = true;
                 return true;
             }
             else if (istreq(ident, "false") ||
                      istreq(ident, "no") ||
                      istreq(ident, "off")) {
-                val_rtrn->uval = 0;
+                *set_rtrn = false;
                 return true;
             }
         }
@@ -260,9 +259,9 @@ ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
 
     case EXPR_INVERT:
     case EXPR_NOT:
-        ok = ExprResolveBoolean(ctx, expr, val_rtrn);
+        ok = ExprResolveBoolean(ctx, expr, set_rtrn);
         if (ok)
-            val_rtrn->uval = !val_rtrn->uval;
+            *set_rtrn = !*set_rtrn;
         return ok;
     case EXPR_ADD:
     case EXPR_SUBTRACT:
@@ -279,6 +278,7 @@ ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
         log_wsgo(ctx, "Unknown operator %d in ResolveBoolean\n", expr->op);
         break;
     }
+
     return false;
 }
 
diff --git a/src/xkbcomp/expr.h b/src/xkbcomp/expr.h
index 9465beb..214ea8d 100644
--- a/src/xkbcomp/expr.h
+++ b/src/xkbcomp/expr.h
@@ -66,9 +66,8 @@ extern int
 ExprResolveVModMask(struct xkb_keymap *keymap, ExprDef *expr,
                     ExprResult *val_rtrn);
 
-extern int
-ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr,
-                   ExprResult *val_rtrn);
+bool
+ExprResolveBoolean(struct xkb_context *ctx, ExprDef *expr, bool *set_rtrn);
 
 extern int
 ExprResolveKeyCode(struct xkb_context *ctx, ExprDef *expr,
diff --git a/src/xkbcomp/symbols.c b/src/xkbcomp/symbols.c
index f196f0b..06db89d 100644
--- a/src/xkbcomp/symbols.c
+++ b/src/xkbcomp/symbols.c
@@ -1110,32 +1110,40 @@ SetSymbolsField(SymbolsInfo *info, KeyInfo *keyi, const char *field,
     }
     else if (istreq(field, "groupswrap") ||
              istreq(field, "wrapgroups")) {
-        if (!ExprResolveBoolean(ctx, value, &tmp)) {
+        bool set;
+
+        if (!ExprResolveBoolean(ctx, value, &set)) {
             log_err(info->keymap->ctx,
                     "Illegal groupsWrap setting for %s; "
                     "Non-boolean value ignored\n",
                     longText(keyi->name));
             return false;
         }
-        if (tmp.uval)
+
+        if (set)
             keyi->out_of_range_group_action = XkbWrapIntoRange;
         else
             keyi->out_of_range_group_action = XkbClampIntoRange;
+
         keyi->defined |= _Key_GroupInfo;
     }
     else if (istreq(field, "groupsclamp") ||
              istreq(field, "clampgroups")) {
-        if (!ExprResolveBoolean(ctx, value, &tmp)) {
+        bool set;
+
+        if (!ExprResolveBoolean(ctx, value, &set)) {
             log_err(info->keymap->ctx,
                     "Illegal groupsClamp setting for %s; "
                     "Non-boolean value ignored\n",
                     longText(keyi->name));
             return false;
         }
-        if (tmp.uval)
+
+        if (set)
             keyi->out_of_range_group_action = XkbClampIntoRange;
         else
             keyi->out_of_range_group_action = XkbWrapIntoRange;
+
         keyi->defined |= _Key_GroupInfo;
     }
     else if (istreq(field, "groupsredirect") ||