feat(analyzer)!: reject mutable dynamic for bounds

Author: tignear

crates/analyzer/src/analyzer.rs

@@ -3,6 +3,7 @@ use crate::attribute_table;
 use crate::comb_loop_detect;
 use crate::conv::{Context, Conv};
 use crate::definition_table;
+use crate::dynamic_for_check;
 use crate::generic_inference_table;
 use crate::handlers::*;
 use crate::ir::{Ir, IrResult};
@@ -266,6 +267,7 @@ impl Analyzer {
 
         ret.append(&mut symbol_table::check_unused_variable());
         ret.append(&mut symbol_table::check_wavedrom());
+        ret.append(&mut dynamic_for_check::check(ir));
         ret.append(&mut comb_loop_detect::check(ir));
 
         ret

crates/analyzer/src/analyzer_error.rs

@@ -3674,6 +3674,8 @@ pub enum InvalidForRangeKind {
     BareExpression,
     /// A range bound elaborates to a negative value.
     NegativeBound,
+    /// The loop body can visibly change an input of the continuation bound.
+    MutableBound,
 }
 
 impl InvalidForRangeKind {
@@ -3683,6 +3685,9 @@ impl InvalidForRangeKind {
             InvalidForRangeKind::NegativeBound => {
                 "for-loop range bounds are elaborated as unsigned; rewrite the range to start at 0 and offset inside the body"
             }
+            InvalidForRangeKind::MutableBound => {
+                "move the assignment outside the loop or iterate over a separate, stable bound"
+            }
         }
     }
 }
@@ -3695,6 +3700,9 @@ impl fmt::Display for InvalidForRangeKind {
                     .fmt(f)
             }
             InvalidForRangeKind::NegativeBound => "for-loop range bound is negative".fmt(f),
+            InvalidForRangeKind::MutableBound => {
+                "for-loop continuation bound is modified by the loop body".fmt(f)
+            }
         }
     }
 }