On Wed, May 16, 2018 at 11:35:56AM -0400, Jason Merrill wrote: > On Wed, May 16, 2018 at 11:15 AM, Marek Polacek <pola...@redhat.com> wrote: > > This PR has been on my mind for quite some time but I've not found a > > solution > > that I'd like. Maybe one of you can think of something better. > > > > The problem in this test is that in C++11, .eh optimizes out the catch, > > so the exception is never caught. That is because lower_catch doesn't > > think that the region may throw (eh_region_may_contain_throw). That's > > so because P::P () is marked as TREE_NOTHROW, which is wrong, because > > it calls X::X() which calls init() with throw. TREE_NOTHROW is set in > > finish_function: > > > > /* If this function can't throw any exceptions, remember that. */ > > if (!processing_template_decl > > && !cp_function_chain->can_throw > > && !flag_non_call_exceptions > > && !decl_replaceable_p (fndecl)) > > TREE_NOTHROW (fndecl) = 1; > > > > P::P() should have been marked as can_throw in set_flags_from_callee, but > > when > > processing X::X() cfun is null, so we can't set it. P::P() is created only > > later via implicitly_declare_fn. > > This should be handled by bot_manip (under break_out_target_exprs, > under get_nsdmi), but it seems that it currently only calls > set_flags_from_callee for CALL_EXPR, not for AGGR_INIT_EXPR as we have > in this case.
Ah, nice! So, this tweaks set_flags_from_callee to also work for AGGR_INIT_EXPRs. Bootstrapped/regtested on x86_64-linux, ok for trunk? 2018-05-16 Marek Polacek <pola...@redhat.com> PR c++/85363 * call.c (set_flags_from_callee): Handle AGGR_INIT_EXPRs too. * tree.c (bot_manip): Call set_flags_from_callee for AGGR_INIT_EXPRs too. * g++.dg/cpp0x/initlist-throw1.C: New test. * g++.dg/cpp0x/initlist-throw2.C: New test. diff --git gcc/cp/call.c gcc/cp/call.c index 09a3618b007..11b40747932 100644 --- gcc/cp/call.c +++ gcc/cp/call.c @@ -319,16 +319,23 @@ build_call_n (tree function, int n, ...) void set_flags_from_callee (tree call) { - bool nothrow; - tree decl = get_callee_fndecl (call); + /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */ + tree decl = cp_get_callee_fndecl_nofold (call); /* We check both the decl and the type; a function may be known not to throw without being declared throw(). */ - nothrow = decl && TREE_NOTHROW (decl); - if (CALL_EXPR_FN (call)) - nothrow |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call)))); - else if (internal_fn_flags (CALL_EXPR_IFN (call)) & ECF_NOTHROW) - nothrow = true; + bool nothrow = decl && TREE_NOTHROW (decl); + if (TREE_CODE (call) == CALL_EXPR) + { + if (CALL_EXPR_FN (call)) + nothrow + |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call)))); + else if (internal_fn_flags (CALL_EXPR_IFN (call)) & ECF_NOTHROW) + nothrow = true; + } + else if (AGGR_INIT_EXPR_FN (call)) + nothrow + |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (AGGR_INIT_EXPR_FN (call)))); if (!nothrow && at_function_scope_p () && cfun && cp_function_chain) cp_function_chain->can_throw = 1; diff --git gcc/cp/tree.c gcc/cp/tree.c index ecb88df23b9..db81da91676 100644 --- gcc/cp/tree.c +++ gcc/cp/tree.c @@ -2987,7 +2987,7 @@ bot_manip (tree* tp, int* walk_subtrees, void* data_) /* Make a copy of this node. */ t = copy_tree_r (tp, walk_subtrees, NULL); - if (TREE_CODE (*tp) == CALL_EXPR) + if (TREE_CODE (*tp) == CALL_EXPR || TREE_CODE (*tp) == AGGR_INIT_EXPR) set_flags_from_callee (*tp); if (data.clear_location && EXPR_HAS_LOCATION (*tp)) SET_EXPR_LOCATION (*tp, input_location); diff --git gcc/testsuite/g++.dg/cpp0x/initlist-throw1.C gcc/testsuite/g++.dg/cpp0x/initlist-throw1.C index e69de29bb2d..264c6c7a7a0 100644 --- gcc/testsuite/g++.dg/cpp0x/initlist-throw1.C +++ gcc/testsuite/g++.dg/cpp0x/initlist-throw1.C @@ -0,0 +1,29 @@ +// PR c++/85363 +// { dg-do run { target c++11 } } + +int +init (int f) +{ + throw f; +} + +struct X { + X (int f) : n {init (f)} {} + int n; +}; + +struct P { + X x{20}; +}; + +int +main () +{ + try { + P p {}; + } + catch (int n) { + return 0; + } + return 1; +} diff --git gcc/testsuite/g++.dg/cpp0x/initlist-throw2.C gcc/testsuite/g++.dg/cpp0x/initlist-throw2.C index e69de29bb2d..2bb05834d9e 100644 --- gcc/testsuite/g++.dg/cpp0x/initlist-throw2.C +++ gcc/testsuite/g++.dg/cpp0x/initlist-throw2.C @@ -0,0 +1,33 @@ +// PR c++/85363 +// { dg-do run { target c++11 } } + +int +init (int f) +{ + throw f; +} + +struct X { + X () : n {init (42)} {} + int n; +}; + +struct P { + struct R { + struct Q { + X x = {}; + } q; + } r; +}; + +int +main () +{ + try { + P p {}; + } + catch (int n) { + return 0; + } + return 1; +}