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Struct assignment

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Hi,
In gcc-4.7 C99, i get an error (in a function scope):

   struct {
       int a;
   } sa;

   struct {
       int a;
   } sb;

   sb = sa;

error: incompatible types when assigning to type 'struct <anonymous>' from type 
'struct <anonymous>'


ISO/IEC 9899:201x Committee Draft -- August 11, 2008 WG14/N1336

6.5.16.1 Simple assignment
Para 1
-- the left operand has a qualified or unqualified version of a structure or 
union type compatible with the type of the right;


6.2.7 Compatible type and composite type
Para 1
Two types have compatible type if their types are the same. Additional rules for 
determining whether two types are compatible are described in 6.7.2 for type 
specifiers, in 6.7.3 for type qualifiers, and in 6.7.5 for declarators.48) 
Moreover, two structure, union, or enumerated types declared in separate 
translation units are compatible if their tags and members satisfy the following 
requirements: If one is declared with a tag, the other shall be declared with 
the same tag. If both are complete types, then the following additional 
requirements apply: there shall be a one-to-one correspondence between their 
members such that each pair of corresponding members are declared with 
compatible types, and such that if one member of a corresponding pair is 
declared with a name, the other member is declared with the same name. For two 
structures, corresponding members shall be declared in the same order. For two 
structures or unions, corresponding bit-fields shall have the same widths. For 
two enumerations, corresponding members shall have the same values.


The above mentions "separate translation units", but i don't see why the error 
should happen.

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Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-19 23:09 +1100
  Re: Struct assignment Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-01-19 08:27 -0500
    Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-20 01:18 +1100
      Re: Struct assignment "BartC" <bc@freeuk.com> - 2013-01-19 14:59 +0000
      Re: Struct assignment Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-01-19 11:25 -0500
        Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-20 12:46 +1100
          Re: Struct assignment Bart van Ingen Schenau <bart@ingen.ddns.info.invalid> - 2013-01-20 09:20 +0000
          Re: Struct assignment Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-01-20 09:08 -0500
            Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-21 12:02 +1100
              Re: Struct assignment Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-01-20 22:08 -0500
                Re: Struct assignment James Kuyper <jameskuyper@verizon.net> - 2013-01-20 23:21 -0500
              Re: Struct assignment James Kuyper <jameskuyper@verizon.net> - 2013-01-21 08:23 -0500
                Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-22 13:33 +1100
                Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-23 19:53 +1100
      Re: Struct assignment Shao Miller <sha0.miller@gmail.com> - 2013-01-19 11:45 -0500
        Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-20 13:21 +1100
          Re: Struct assignment Shao Miller <sha0.miller@gmail.com> - 2013-01-20 01:06 -0500
            Re: Struct assignment Russell Shaw <rjshawN_o@s_pam.netspace.net.au> - 2013-01-20 18:03 +1100
  Re: Struct assignment glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-01-19 19:18 +0000
    Re: Struct assignment James Kuyper <jameskuyper@verizon.net> - 2013-01-19 15:22 -0500
      Re: Struct assignment Shao Miller <sha0.miller@gmail.com> - 2013-01-19 15:47 -0500
      Re: Struct assignment Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-01-19 17:56 -0500
        Re: Struct assignment Tim Rentsch <txr@alumni.caltech.edu> - 2013-01-20 12:12 -0800
  Re: Struct assignment falk@rahul.net (Edward A. Falk) - 2013-01-19 23:41 +0000
    Re: Struct assignment glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-01-20 01:01 +0000
    Re: Struct assignment James Kuyper <jameskuyper@verizon.net> - 2013-01-19 20:53 -0500
      Re: Struct assignment Tim Rentsch <txr@alumni.caltech.edu> - 2013-01-20 12:03 -0800

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