Bug 540047

Summary: Can't use labeled elements in initializers for structs with unnamed union fields
Product: [Fedora] Fedora Reporter: Casey Dahlin <cdahlin>
Component: gccAssignee: Jakub Jelinek <jakub>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: low    
Version: 12CC: jakub, vanhoof
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OS: Linux   
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Last Closed: 2009-11-23 07:49:10 UTC Type: ---
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Reproducer none

Description Casey Dahlin 2009-11-22 02:07:14 UTC 
Created attachment 372842 [details]
Reproducer

Description of problem:
If you try to use a struct with an unnamed union field, for example:

struct foo {
  int bar;
  union {
    int baz;
    int bam;
  };
};

And then try to statically initialize one using field labels like so:

struct foo mine = { .bar = 1, .baz = 2 };

you get:

error: unknown field ‘baz’ specified in initializer

Version-Release number of selected component (if applicable):
gcc-4.4.2-7.fc12

Steps to Reproduce:
Try compiling the attached program.
  
Actual results:
reproducer.c:13: error: unknown field ‘baz’ specified in initializer

Expected results:
Compiles. mine.bar == 1, mine.baz == mine.bam == 2
Comment 1 Jakub Jelinek 2009-11-23 07:49:10 UTC 
Why do you think it is a bug?  ISO C99 designated initializers require that the identifier identifies a field in the current structure/union, which is not the case.