[cfe-dev] Designated initialization warns if struct members are not in declaration order

Sascha Wildner swildner at erpicon.de
Thu Oct 16 15:50:54 PDT 2008

Hello list,

ยง6.7.8/17 of ISO/IEC 9899:1999 says:

"Each brace-enclosed initializer list has an associated current object. 
When no designations are present, subobjects of the current object are 
initialized in order according to the type of the current object: array 
elements in increasing subscript order, structure members in declaration 
order, and the first named member of a union. In contrast, a designation 
causes the following initializer to begin initialization of the 
subobject described by the designator. Initialization then continues 
forward in order, beginning with the next subobject after that described 
by the designator."

However, clang seems to expect the structure members to be initialized 
in declaration order. Hence, the following test program will issue warnings:

static int
test_funca(int *a)
         return *a;

static int
test_funcb(char *b)
         *b = 'a';

         return 1;

struct test_ops {
         int     (*test_a)(int *);
         int     (*test_b)(char *);

struct test_ops test = {
         .test_b = test_funcb,
         .test_a = test_funca

         return 0;

Swapping .test_b and .test_a in the initialization will silence the 


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