https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65301
Bug ID: 65301 Summary: gcc can't detect some uninit reads in ctor init lists Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: dcb314 at hotmail dot com Given the following source code class K { public: K * copy(); }; class FunctionExpr { public: FunctionExpr( const FunctionExpr & ); private: K * args; }; FunctionExpr::FunctionExpr(const FunctionExpr& expr) : args(expr.args ? args->copy() : 0) { } then trunk gcc can't detect the read of uninit memory for args->copy. $ ~/gcc/results/bin/gcc -c -g -O2 -Wall -Wextra -pedantic bug189.cc $ Here is clang doing the right thing: $ ~/llvm/results/bin/clang++ -c -g -O2 -Wall -Wextra -pedantic bug189.cc bug189.cc:18:28: warning: field 'args' is uninitialized when used here [-Wuninitialized] : args(expr.args ? args->copy() : 0) ^ 1 warning generated. $