diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cp/call.cc | 12 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/warn/Wdangling-reference5.C | 22 |
2 files changed, 33 insertions, 1 deletions
diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index c7c7a12..2c0fa37 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -13467,7 +13467,17 @@ do_warn_dangling_reference (tree expr) can be e.g. const int& z = std::min({1, 2, 3, 4, 5, 6, 7}); which doesn't dangle: std::min here returns an int. */ - || !TYPE_REF_OBJ_P (TREE_TYPE (TREE_TYPE (fndecl)))) + || !TYPE_REF_OBJ_P (TREE_TYPE (TREE_TYPE (fndecl))) + /* Don't emit a false positive for: + std::vector<int> v = ...; + std::vector<int>::const_iterator it = v.begin(); + const int &r = *it++; + because R refers to one of the int elements of V, not to + a temporary object. Member operator* may return a reference + but probably not to one of its arguments. */ + || (DECL_NONSTATIC_MEMBER_FUNCTION_P (fndecl) + && DECL_OVERLOADED_OPERATOR_P (fndecl) + && DECL_OVERLOADED_OPERATOR_IS (fndecl, INDIRECT_REF))) return NULL_TREE; /* Here we're looking to see if any of the arguments is a temporary diff --git a/gcc/testsuite/g++.dg/warn/Wdangling-reference5.C b/gcc/testsuite/g++.dg/warn/Wdangling-reference5.C new file mode 100644 index 0000000..59b5538 --- /dev/null +++ b/gcc/testsuite/g++.dg/warn/Wdangling-reference5.C @@ -0,0 +1,22 @@ +// PR c++/107488 +// { dg-do compile } +// { dg-options "-Wdangling-reference" } + +#include <vector> + +int +do_sum (std::vector<int>& v) +{ + int sum = 0; + + std::vector<int>::const_iterator it = v.begin(); + while (it != v.end()) + { + // R refers to one of the int elements of V, not to a temporary + // object, so no dangling reference here. + const int &r = *it++; // { dg-bogus "dangling reference" } + sum += r; + } + + return sum; +} |