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Newsgroups: comp.lang.ada
Date: Tue, 9 Jul 2019 11:46:06 -0700 (PDT)
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Subject: Re: Odd AVR-Ada code generation issue with constant record type
From: Per Jakobsen <pdj@knaldgas.dk>
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Xref: reader01.eternal-september.org comp.lang.ada:56840
Date: 2019-07-09T11:46:06-07:00
List-Id: <comp.lang.ada>

Just tried with C bitfields:

================================
#include <stdint.h>

struct Reg_T {
        unsigned int a : 3;
        unsigned int b : 1;
        unsigned int c : 4;
} __attribute__((packed));


volatile struct Reg_T Reg_A;
volatile struct Reg_T Reg_B;
volatile struct Reg_T Reg_C;
volatile uint8_t A;
volatile uint8_t B;

void main (void)
{
	Reg_A = (struct Reg_T){ .a = 0, .b = 0, .c = 0 };
	Reg_B = (struct Reg_T){ .a = 0, .b = 1, .c = 0 };
	Reg_C = (struct Reg_T){ .a = 7, .b = 1, .c = 15 }

        A = 0;
        B = 255;
}
================================

Same type of result...
GCC back-end then?