From 13de117b8e52f4d7c1c5e3a0ece89f380d36975b Mon Sep 17 00:00:00 2001
From: florian <florian@freepascal.org>
Date: Sun, 16 Jun 2024 10:51:45 +0200
Subject: [PATCH]   * give better error message for #40821

---
 compiler/msg/errore.msg | 3 +++
 compiler/pdecl.pas      | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler/msg/errore.msg b/compiler/msg/errore.msg
index b6fc0fac24..505caad31f 100644
--- a/compiler/msg/errore.msg
+++ b/compiler/msg/errore.msg
@@ -1679,6 +1679,9 @@ parser_e_nostringaliasinsystem=03370_E_Using 'string' alias is not allowed in th
 parser_e_coperators_off=03371_E_C styled assignment operators are turned off
 % By default, c style assignment operators (+=, -=, *=, /=) are turn off. Either turn them on by the command line
 % parameter -Sc or in the source code by {\$COPERATORS ON}
+parser_e_cannot_evaluate_expression_at_compile_time=03372_E_Expression cannot be evaluted at compile time
+% Certain operations like the size of an object cannot be determined at compile time,
+% so it cannot be e.g. part of a constant expression.
 %
 % \end{description}
 %
diff --git a/compiler/pdecl.pas b/compiler/pdecl.pas
index c35dec9690..dd1dfc2f3e 100644
--- a/compiler/pdecl.pas
+++ b/compiler/pdecl.pas
@@ -174,7 +174,7 @@ implementation
                  information about the final type yet, we need to use safe
                  values (mostly 0, except for (Bit)SizeOf()) }
                if not parse_generic then
-                 Message(parser_e_illegal_expression);
+                 Message(parser_e_cannot_evaluate_expression_at_compile_time);
                case tinlinenode(p).inlinenumber of
                  in_sizeof_x:
                    begin