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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Record initialisation question
Date: Mon, 11 Jan 2021 22:58:57 +0200
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On 2021-01-11 19:46, DrPi wrote:

> I added "pragma No_Elaboration_Code_All;" to my code and... all records 
> are rejected.
> The boot data structure (in FLASH memory) is composed of several 
> records. They are linked by their addresses. When a record contains an 
> address, initializing it with a "non static number" value makes the 
> compiler complain (with No_Elaboration_Code_All set).


Ah, too bad.

The problem is that "static" in Ada means "known at compile time", while 
addresses, although static in execution, are generally not known until 
link time. A case where assembly language is more powerful :-(

> I have to find a workaround.

If addresses are the only problem, and you are in control of the flash 
memory lay-out, you might be able to define static Ada constant 
expressions that compute ("predict") the addresses of every boot data 
structure record. But those expressions would need to use the sizes of 
the records, I think, and unfortunately the 'Size of a record type is 
not a static expression (IIRC), and that may hold also for the 
GNAT-specific 'Max_Size_In_Storage_Units.