diff --git a/astgen.c b/astgen.c
index 45ab95e3e7..040528f9cc 100644
--- a/astgen.c
+++ b/astgen.c
@@ -3033,6 +3033,18 @@ static uint32_t ptrTypeExpr(GenZir* gz, Scope* scope, uint32_t node) {
         }
     }
 
+    // C pointers always allow address zero (AstGen.zig:3840-3842).
+    if (size == 3 && has_allowzero) {
+        SET_ERROR(ag);
+        return ZIR_REF_VOID_VALUE;
+    }
+
+    // Save source cursor before typeExpr so we can restore it before each
+    // trailing expression (AstGen.zig:3844-3846).
+    uint32_t saved_source_offset = ag->source_offset;
+    uint32_t saved_source_line = ag->source_line;
+    uint32_t saved_source_column = ag->source_column;
+
     // Evaluate element type (AstGen.zig:3847).
     uint32_t elem_type = typeExpr(gz, scope, child_type_node);
 
@@ -3045,6 +3057,10 @@ static uint32_t ptrTypeExpr(GenZir* gz, Scope* scope, uint32_t node) {
     uint32_t trailing_count = 0;
 
     if (sentinel_node != UINT32_MAX) {
+        // Restore source cursor (AstGen.zig:3859-3861).
+        ag->source_offset = saved_source_offset;
+        ag->source_line = saved_source_line;
+        ag->source_column = saved_source_column;
         uint32_t reason = (size == 2) ? COMPTIME_REASON_SLICE_SENTINEL
                                       : COMPTIME_REASON_POINTER_SENTINEL;
         ResultLoc srl = {
@@ -3054,6 +3070,10 @@ static uint32_t ptrTypeExpr(GenZir* gz, Scope* scope, uint32_t node) {
         trailing_count++;
     }
     if (addrspace_node != UINT32_MAX) {
+        // Restore source cursor (AstGen.zig:3876-3878).
+        ag->source_offset = saved_source_offset;
+        ag->source_line = saved_source_line;
+        ag->source_column = saved_source_column;
         // Upstream creates addrspace_ty via addBuiltinValue, we don't have
         // that yet, so pass RL_NONE (matching previous behavior).
         addrspace_ref = comptimeExpr(
@@ -3061,6 +3081,10 @@ static uint32_t ptrTypeExpr(GenZir* gz, Scope* scope, uint32_t node) {
         trailing_count++;
     }
     if (align_node != UINT32_MAX) {
+        // Restore source cursor (AstGen.zig:3885-3887).
+        ag->source_offset = saved_source_offset;
+        ag->source_line = saved_source_line;
+        ag->source_column = saved_source_column;
         ResultLoc arl = { .tag = RL_COERCED_TY,
             .data = ZIR_REF_U29_TYPE,
             .src_node = 0,