https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86210
Bug ID: 86210
Summary: [6/7/8/9 Regression] Missing -Wnonnull warning for
function defined in the same TU
Product: gcc
Version: 8.1.1
Status: UNCONFIRMED
Keywords: diagnostic
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
Target Milestone: ---
void * declared_not_defined(void * p) __attribute__((nonnull));
inline void * declared_and_defined(void * p) __attribute__((nonnull));
int main()
{
int * const p = 0;
declared_not_defined(p);
declared_and_defined(p);
}
void * declared_and_defined(void * p) { return p; }
G++ 5 and 6 fail to give any warnings at all, at any optimisation level.
G++ 7 and 8 and trunk only warn at -O1 and higher, and only for one of the two
calls:
x.cc: In function ‘int main()’:
x.cc:8:25: warning: argument 1 null where non-null expected [-Wnonnull]
declared_not_defined(p);
~~~~~~~~~~~~~~~~~~~~^~~
x.cc:1:8: note: in a call to function ‘void* declared_not_defined(void*)’
declared here
void * declared_not_defined(void * p) __attribute__((nonnull));
^~~~~~~~~~~~~~~~~~~~
G++ 4.7, 4.8 and 4.9 warns about both calls, without any optimisation:
x.cc: In function ‘int main()’:
x.cc:8:27: warning: null argument where non-null required (argument 1)
[-Wnonnull]
declared_not_defined(p);
^
x.cc:9:27: warning: null argument where non-null required (argument 1)
[-Wnonnull]
declared_and_defined(p);
^
Compiling it as C gives almost the opposite results! I get no warnings for any
release before 7.1, and a warning for only one function with 7.1 but only with
optimisation, and warnings for both function for 8.1 with optimisation. So for
C thigns have been getting gradually better, but worse for C++.
