diff --git a/CHANGES b/CHANGES
index 5b6449c87..0d666072c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,42 @@
+1.12.0-dev.150 | 2024-10-17 10:16:57 +0200
+
+  * GH-1792: Prioritize error message reporting unknown field. (Robin Sommer, Corelight)
+
+    This suppresses some non-interesting follow-up errors.
+
+  * GH-1790: Provide proper error message when trying access an unknown unit field. (Robin Sommer, Corelight)
+
+    Returning `type::Unknown` instead of `type::Auto` will let the
+    resolver process stop, allowing an already existing error message to
+    kick in later. We were doing it this way already for structs, but not
+    for units.
+
+    This also includes a fix for a bug with finding bitfield ranges by ID,
+    which was triggered by the change.
+
+  * GH-1791: Fix usage of `&convert` with unit's requiring parameters. (Robin Sommer, Corelight)
+
+    The generated code needs to create a temporary instance of the type,
+    but doesn't have any arguments to provide to it. But that's ok, and we
+    now let the validation pass and just instantiate a default-constructed
+    instance.
+
+    However, this change now requires an additional validator check on the
+    Spicy side to ensure fields giving arguments to types do so correctly
+    Before we happened to check that implicitly on the HILTI-side through
+    code that now would let it pass if no arguments were given.
+
+  * Factor out logic to validate arguments given to a type. (Robin Sommer, Corelight)
+
+    This will allow Spicy's validator to use it as well.
+
+    We also add two options to (1) accept usages where no argument is given at
+    all even when the type would normally require it,;and (2) skip any
+    actual type checking, and just confirm argument count. In a subsequent
+    change, we'll use (1) to fall-back to a type's default constructor,
+    and (2) to check type usage inside unit fields where we haven't
+    fully coerced arguments yet.
+
 1.12.0-dev.144 | 2024-10-16 16:10:40 +0200
 
   * GH-1861: Disallow ignored attributes on type aliases. (Evan Typanski, Corelight)
diff --git a/VERSION b/VERSION
index 9b0333320..3de6e6018 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.12.0-dev.144
+1.12.0-dev.150
diff --git a/spicy/toolchain/src/ast/operators/unit.cc b/spicy/toolchain/src/ast/operators/unit.cc
index 37da54aeb..fddbf5b1f 100644
--- a/spicy/toolchain/src/ast/operators/unit.cc
+++ b/spicy/toolchain/src/ast/operators/unit.cc
@@ -18,7 +18,7 @@ void checkName(hilti::expression::ResolvedOperator* op) {
     auto i = op->op0()->type()->type()->as<type::Unit>()->itemByName(id);
 
     if ( ! i )
-        op->addError(hilti::util::fmt("unit does not have field '%s'", id));
+        op->addError(hilti::util::fmt("unit does not have field '%s'", id), node::ErrorPriority::High);
 }
 
 
@@ -31,7 +31,7 @@ QualifiedType* itemType(hilti::Builder* builder, const Expressions& operands) {
     else if ( auto bitrange = unit->findRangeInAnonymousBitField(id).second )
         return bitrange->itemType();
     else
-        return builder->qualifiedType(builder->typeAuto(), hilti::Constness::Const);
+        return builder->qualifiedType(builder->typeUnknown(), hilti::Constness::Const);
 }
 
 QualifiedType* contextResult(hilti::Builder* builder, const Expressions& operands, hilti::Constness constness) {
diff --git a/spicy/toolchain/src/ast/types/unit.cc b/spicy/toolchain/src/ast/types/unit.cc
index 77d1c8d03..265c282af 100644
--- a/spicy/toolchain/src/ast/types/unit.cc
+++ b/spicy/toolchain/src/ast/types/unit.cc
@@ -97,7 +97,7 @@ static std::pair<unit::item::Field*, hilti::type::bitfield::BitRange*> findRange
             if ( ! field->isAnonymous() )
                 continue;
 
-            auto t = field->itemType()->type()->tryAs<hilti::type::Bitfield>();
+            auto t = field->originalType()->type()->tryAs<hilti::type::Bitfield>();
             if ( ! t )
                 continue;
 
diff --git a/tests/Baseline/spicy.types.unit.unknown-field-2/output b/tests/Baseline/spicy.types.unit.unknown-field-2/output
new file mode 100644
index 000000000..a24d2ab59
--- /dev/null
+++ b/tests/Baseline/spicy.types.unit.unknown-field-2/output
@@ -0,0 +1,3 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
+[error] <...>/unknown-field.spicy:12:16-12:23: unit does not have field 'tss'
+[error] spicyc: aborting after errors
diff --git a/tests/Baseline/spicy.types.unit.unknown-field/output b/tests/Baseline/spicy.types.unit.unknown-field/output
new file mode 100644
index 000000000..7c0390639
--- /dev/null
+++ b/tests/Baseline/spicy.types.unit.unknown-field/output
@@ -0,0 +1,3 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
+[error] <...>/unknown-field.spicy:13:14-13:22: unit does not have field 'bar_'
+[error] spicyc: aborting after errors
diff --git a/tests/spicy/types/unit/unknown-field.spicy b/tests/spicy/types/unit/unknown-field.spicy
new file mode 100644
index 000000000..3989c44d1
--- /dev/null
+++ b/tests/spicy/types/unit/unknown-field.spicy
@@ -0,0 +1,32 @@
+# @TEST-EXEC-FAIL: spicyc -p %INPUT >output 2>&1
+# @TEST-EXEC: btest-diff output
+#
+# @TEST-DOC: Check that we get a proper error message when trying to access an unknown unit field; regression test for #1790 and #1792
+
+module Test;
+
+type Msg = unit {
+  var x: uint16;
+  bar: uint16;
+
+  on %done {
+    self.x = self.bar_;
+  }
+};
+
+# @TEST-START-NEXT
+
+module Test;
+
+type T = unit() {
+  x: uint8;
+};
+
+public type U = unit() {
+  len: uint32;
+
+  ts: T[] &size=self.len {
+    for ( e in self.tss )
+      print e.x;
+  }
+};