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digitalmars.D.bugs - [Issue 1432] New: Bogus "overlapping initialization" error with structs, unions, and member initializers

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1432

           Summary: Bogus "overlapping initialization" error with structs,
                    unions, and member initializers
           Product: D
           Version: 1.018
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla digitalmars.com
        ReportedBy: jarrett.billingsley gmail.com


struct S
{
        int blah = 5;

        union
        {
                int x;
                T t;
                Object o;
        }
}

struct T
{
        int y;
}

Gives the error "dtest.d(26): struct dtest.S overlapping initialization for
struct S.blah"

If you remove the initializer for S.blah, or if you remove the t member from
that union, or if you make the union named, it works.


-- 
Aug 19 2007
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1432






Another variation:

union S
{
    float[2] a;
    struct
    {
        union { float i = 1; float x; }
        union { float j = 2; float y; }
    }
}

$ dmd bar.d -c
bar.d(2): Error: union bar.S overlapping initialization for struct S.i
bar.d(2): Error: union bar.S overlapping initialization for struct S.j

If 'a' is moved below the anonymous struct it works. The spec does not mention
this special case as far as I can tell. Explicit initialization of aggregate
fields inside anonymous struct/union combinations should be documented.


-- 
Apr 22 2009
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1432


Trass3r <mrmocool gmx.de> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |mrmocool gmx.de
           Platform|x86                         |All
         OS/Version|Windows                     |All



The first example compiles fine now.
Really not sure if the second should compile at all, but the order of
compilation dependence is definitely a bug.

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Nov 27 2011
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1432





 Another variation:
 
 union S
 {
     float[2] a;
     struct
     {
         union { float i = 1; float x; }
         union { float j = 2; float y; }
     }
 }
 
 $ dmd bar.d -c
 bar.d(2): Error: union bar.S overlapping initialization for struct S.i
 bar.d(2): Error: union bar.S overlapping initialization for struct S.j
 
 If 'a' is moved below the anonymous struct it works. The spec does not mention
 this special case as far as I can tell. Explicit initialization of aggregate
 fields inside anonymous struct/union combinations should be documented.
More reduced test case. union U1 { int a = 1; // OK string b; } union U2 { int a; string b = "s"; // overlapping initialization for struct U2.b } I discovered this behavior while debugging other compiler bug. If there's overlapped fields, and the non-first field is explicitly initialized, compiler rejects it by "overlapping initialization". As far as I see, the behavior seems to be intended by the current compiler code. However, normally D language semantics does not rely on the lexical order of declarations. I can agree that the behavior is contrary to the basic principle. --- I'd propose more better semantics: If exactly one field has an explicit initializer between overlapped fields, compiler should prefer it for default initialization. U1 u1; assert(u1.a == 1); U2 u2; assert(u2.b == "s"); If there's no explicitly initialized field between overlapped siblings, the first one is initialized at the default initialization. union U3 { int a; char c; } U3 u3; assert(u3.a == 0); union U4 { char c; int a; } U4 u4; assert(u4.c == 0xff); If two or more fields have explicit initializers between overlapped siblings, it would cause compilation error. union U5 { int a = 1, string b = "s" } U5 u5; // Error: overlapped initialization between U5.a and U5.b How about that? -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Oct 01 2013
prev sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=1432


Kenji Hara <k.hara.pg gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|1.018                       |D2



Change to D2 issue.

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