https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69433
Bug ID: 69433
Summary: missing -Wreturn-local-addr assigning address of a
local to a static
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: msebor at gcc dot gnu.org
Target Milestone: ---
Gcc issues the helpful -Wreturn-local-addr warning for the first two functions
in the test case below but not for for the second two. It would be useful if
the same or similar warning (say something like -Wleak-local-addr) were issued
there as well. (Note that Clang only diagnoses f0.)
$ cat z.cpp && ~/bin/gcc-5.1.0/bin/g++ -O2 -S -Wall -Wextra -Wpedantic
-o/dev/null z.cpp
const char* f0 () {
const char a[] = "abc";
return a;
}
const char* f1 (int i) {
const char a[] = "abc";
const char *q = i ? a : "def";
return q;
}
const char* f2 () {
const char a[] = "abc";
static const char *s = a;
return s;
}
static const char *s;
void f3 () {
const char a[] = "abc";
s = a;
}
z.cpp: In function ‘const char* f0()’:
z.cpp:2:16: warning: address of local variable ‘a’ returned
[-Wreturn-local-addr]
const char a[] = "abc";
^
z.cpp: In function ‘const char* f1(int)’:
z.cpp:9:12: warning: function may return address of local variable
[-Wreturn-local-addr]
return q;
^
z.cpp:7:16: note: declared here
const char a[] = "abc";
^
