I've initialized an array of structs with three items and it is showing 2 for me !!!
#include <stdio.h>
typedef struct record {
int value;
char *name;
} record;
int main (void) {
record list[] = { (1, "one"), (2, "two"), (3, "three") };
int n = sizeof(list) / sizeof(record);
printf("list's length: %i \n", n);
return 0;
}
What is happening here? Am I getting crazy?
Change initialization to:
record list[] = { {1, "one"}, {2, "two"}, {3, "three"} };
/* ^ ^ ^ ^ ^ ^ */
Your initialization with (...) leaves effect similar to {"one", "two", "three"} and creates a struct array with elements { {(int)"one", "two"}, {(int)"three", (char *)0} }
comma operator in C evaluates the expressions from left to right and discard all except the last. This is the reason why 1, 2 and 3 are discarded.
sizeof(list) returns 16 when initialized the wrong way?
You are not initializing list properly. Putting initializing elements in () will let the compiler to treat , as comma operator instead of separator.
Your compiler should give these warnings
[Warning] left-hand operand of comma expression has no effect [-Wunused-value]
[Warning] missing braces around initializer [-Wmissing-braces]
[Warning] (near initialization for 'list[0]') [-Wmissing-braces]
[Warning] initialization makes integer from pointer without a cast [enabled by default]
[Warning] (near initialization for 'list[0].value') [enabled by default]
[Warning] left-hand operand of comma expression has no effect [-Wunused-value]
[Warning] left-hand operand of comma expression has no effect [-Wunused-value]
[Warning] initialization makes integer from pointer without a cast [enabled by default]
[Warning] (near initialization for 'list[1].value') [enabled by default]
[Warning] missing initializer for field 'name' of 'record' [-Wmissing-field-initializers]
Initialization should be done as
record list[] = { {1, "one"}, {2, "two"}, {3, "three"} };
record list[]properly.