Slightly improve warning about unreachable for-statements.

[r21493]

diff --git a/parser.c b/parser.c
index b236a13..07f1141 100644 (file)
--- a/parser.c
+++ b/parser.c
@@ -5004,8 +5004,7 @@ static void check_unreachable(statement_t const* const stmt)
            stmt->kind != STATEMENT_COMPOUND &&
            stmt->kind != STATEMENT_DO_WHILE &&
            stmt->kind != STATEMENT_FOR) {
-               warningf(&stmt->base.source_position,
-                        "statement is unreachable");
+               warningf(&stmt->base.source_position, "statement is unreachable");
        }
 
        switch (stmt->kind) {
@@ -5062,19 +5061,24 @@ static void check_unreachable(statement_t const* const stmt)
                case STATEMENT_FOR: {
                        for_statement_t const* const fors = &stmt->fors;
 
-                       if (!stmt->base.reachable && fors->initialisation != NULL) {
-                               warningf(&fors->initialisation->base.source_position,
-                                        "initialisation of for-statement is unreachable");
-                       }
+                       // if init and step are unreachable, cond is unreachable, too
+                       if (!stmt->base.reachable && !fors->step_reachable) {
+                               warningf(&stmt->base.source_position, "statement is unreachable");
+                       } else {
+                               if (!stmt->base.reachable && fors->initialisation != NULL) {
+                                       warningf(&fors->initialisation->base.source_position,
+                                                "initialisation of for-statement is unreachable");
+                               }
 
-                       if (!fors->condition_reachable && fors->condition != NULL) {
-                               warningf(&fors->condition->base.source_position,
-                                        "condition of for-statement is unreachable");
-                       }
+                               if (!fors->condition_reachable && fors->condition != NULL) {
+                                       warningf(&fors->condition->base.source_position,
+                                                "condition of for-statement is unreachable");
+                               }
 
-                       if (!fors->step_reachable && fors->step != NULL) {
-                               warningf(&fors->step->base.source_position,
-                                        "step of for-statement is unreachable");
+                               if (!fors->step_reachable && fors->step != NULL) {
+                                       warningf(&fors->step->base.source_position,
+                                                "step of for-statement is unreachable");
+                               }
                        }
 
                        check_unreachable(stmt->fors.body);