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MODULE M; TYPE T1 = POINTER TO T1Desc; T1Desc = RECORD END; T2 = POINTER TO T2Desc; T2Desc = RECORD(T1Desc) END; VAR t1: T1; t2: T2; PROCEDURE P1(t: T1); END P1; PROCEDURE P2(VAR t: T1); END P2; BEGIN t1 := t2; P1(t2); P2(t2) (* does not compile *) END M. I am not sure why the compiler rejects the ...

Oh, that's a bit disappointing. In my book, being able to extend a base type without the need to change this base type scores high. Again, is this a limitation of the language or the compiler? Here's a loosely related follow-up issue I ran into today: MODULE M1; TYPE T1 = POINTER TO T1Desc; T1Desc =...

Let's assume we have this module as starting point: MODULE M1; TYPE T1* = POINTER TO T1Desc; T1Desc* = RECORD i: INTEGER END; PROCEDURE P1*(t: T1); END P1; PROCEDURE Init*(t: T1); BEGIN t.i := 13 END Init; END M1. Now I want to extend the type as follows: MODULE M2; IMPORT M1; TYPE T2* = POINTER TO ...

Is NIL represented as 0 (zero), ie. does 'returning NIL' mean assigning zero to 'p' in Storage.Allocate()? (That's what I would infer from Storage.Deallocate().)

The Oberon Report (2016) states for NEW(): "Failure of allocation results in p obtaining the value NIL." (6.4 Pointer Types). Storage.Allocate() has an ASSERT to check for heap overflow (which halts execution as per the standard Error module). Is Storage.Allocate() an exact representation of the com...

But I could write this, right? PROCEDURE NMITrap[0]; VAR trapAddr: INTEGER; BEGIN SYSTEM.GET(SYSTEM.SP + 68, trapAddr); ... Note the [0] and changed SP-offset, as on entry to a normal interrupt handler you also save the other eight registers R4 to R11, I think. I want to use this with SVCTrap to all...

I try to figure out the structure of the stack frame for exception handlers (STM32F207 target, or M3 in general, I guess). The programming manual explains the "stacking", but is not specific regarding the order the listed items are put on the stack: R0-R3, return address, PSR, LR. Based on the code ...

Thanks.

cfbsoftware wrote: P.S. I had to remove your modules.zip attachment as it contained a significant amount of source code which can only be shared with other Astrobe Personal and Professional users.

Oops. Sorry about that.

1. No, I have not modified Storage.mod. 2. The config is the stock one, aside from the library search paths. 3. When I run your program with the stock Main.mod, I get the same memory values as you. 4. However, I use a slightly modified Main.mod, as well as a modified Serial.mod (Serial2.mod, allowin...

I am baffled by the following behaviour (Cortex M3, STM32F207 target). Here's a minimal test case, condensed and abstracted from my actual code. MODULE testalloc; IMPORT Main, Out; TYPE P = POINTER TO Pdesc; Pdesc = RECORD i: INTEGER END; VAR p: P; BEGIN NEW(p); p.i := 13; Out.Int(p.i, 0); Out.Ln EN...