https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80194
Bug ID: 80194 Summary: ICE with local constant referenced by a lambda expression Product: gcc Version: 5.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: curlypaul924 at gmail dot com Target Milestone: --- The following causes an ICE on g++ 5.4.0 and on the latest gcc-5-branch. It does not ICE on 6.0 or later. int fn1(); template <class Fn> void fn2(Fn &&fn) { fn(42); } void fn2() { auto const x = fn1(); fn2([&](auto) { x; }); } Building with -std=c++14, the output is: test.cpp: In instantiation of ‘fn2()::<lambda(auto:1)> [with auto:1 = int]’: test.cpp:4:5: required from ‘void fn2(Fn&&) [with Fn = fn2()::<lambda(auto:1)>]’ test.cpp:9:23: required from here test.cpp:9:19: internal compiler error: Segmentation fault fn2([&](auto) { x; }); ^ 0xaab7ff crash_signal ../.././gcc/toplev.c:383 0x70ac4c maybe_constant_init(tree_node*, tree_node*) ../.././gcc/cp/constexpr.c:4097 0x6320bf tsubst_copy ../.././gcc/cp/pt.c:13180 0x622c68 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool, bool) ../.././gcc/cp/pt.c:15797 0x62b392 tsubst_expr ../.././gcc/cp/pt.c:14606 0x62a4f6 tsubst_expr ../.././gcc/cp/pt.c:14017 0x62b2dc tsubst_expr ../.././gcc/cp/pt.c:14189 0x62b2dc tsubst_expr ../.././gcc/cp/pt.c:14189 0x62a09d instantiate_decl(tree_node*, int, bool) ../.././gcc/cp/pt.c:20675 0x6597d2 mark_used(tree_node*, int) ../.././gcc/cp/decl2.c:5122 0x5f889b build_over_call ../.././gcc/cp/call.c:7545 0x5fafd1 build_op_call_1 ../.././gcc/cp/call.c:4347 0x5fafd1 build_op_call(tree_node*, vec<tree_node*, va_gc, vl_embed>**, int) ../.././gcc/cp/call.c:4370 0x6c3118 finish_call_expr(tree_node*, vec<tree_node*, va_gc, vl_embed>**, bool, bool, int) ../.././gcc/cp/semantics.c:2426 0x624d46 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool, bool) ../.././gcc/cp/pt.c:15434 0x62b392 tsubst_expr ../.././gcc/cp/pt.c:14606 0x62a4f6 tsubst_expr ../.././gcc/cp/pt.c:14017 0x62b2dc tsubst_expr ../.././gcc/cp/pt.c:14189 0x62a09d instantiate_decl(tree_node*, int, bool) ../.././gcc/cp/pt.c:20675 0x63edeb instantiate_pending_templates(int) ../.././gcc/cp/pt.c:20792 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. Output of g++ -v: Using built-in specs. COLLECT_GCC=/home/pbrannan/opt/gcc-5-branch/bin/g++ COLLECT_LTO_WRAPPER=/home/pbrannan/opt/gcc-5-branch/libexec/gcc/x86_64-unknown-linux-gnu/5.4.1/lto-wrapper Target: x86_64-unknown-linux-gnu Configured with: ./configure --disable-multilib --prefix=/home/pbrannan/opt/gcc-5-branch : (reconfigured) ./configure --disable-multilib --prefix=/home/pbrannan/opt/gcc-5-branch --enable-languages=c,c++,fortran,java,lto,objc --no-create --no-recursion Thread model: posix gcc version 5.4.1 20170326 (GCC)