https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71742
Bug ID: 71742
Summary: Wrong formulation of "error: flexible array member in
otherwise empty struct"
Product: gcc
Version: 7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: ch3root at openwall dot com
Target Milestone: ---
Source code:
----------------------------------------------------------------------
int main()
{
struct s {
int :1;
int a[];
};
}
----------------------------------------------------------------------
Results:
----------------------------------------------------------------------
$ gcc -std=c11 -pedantic -Wall -Wextra -O3 test.c && ./a.out
test.c: In function ‘main’:
test.c:5:9: error: flexible array member in otherwise empty struct
int a[];
^
----------------------------------------------------------------------
gcc version: gcc (GCC) 7.0.0 20160627 (experimental)
gcc is right in detecting an error in this testcase but the message is wrong
because the struct is not otherwise empty. The problem is absence of named
members.
The relevant rule:
C11, 6.7.2.1p18: "As a special case, the last element of a structure with more
than one named member may have an incomplete array type; this is called a
flexible array member."
