From e60032b382364897a58e67994baac896bcd03327 Mon Sep 17 00:00:00 2001 From: Nathaniel Shead Date: Tue, 30 Apr 2024 22:29:57 +1000 Subject: c++/modules: Stream unmergeable temporaries by value again [PR114856] In r14-9266-g2823b4d96d9ec4 I gave all temporary vars a DECL_CONTEXT, including those at namespace or global scope, so that they could be properly merged across importers. However, not all of these temporary vars are actually supposed to be mergeable. For instance, in the attached testcase we have an unnamed temporary var used in the NSDMI of a class member, which cannot properly merged -- but it also doesn't need to be, as it'll be thrown away when the class type itself is merged anyway. This patch reverts the change made above and instead makes a weaker adjustment that only causes temporary vars with linkage have a DECL_CONTEXT to merge from. This way these unnamed, "unmergeable" temporaries are properly streamed by value again. PR c++/114856 gcc/cp/ChangeLog: * call.cc (make_temporary_var_for_ref_to_temp): Set context for temporaries with linkage. * init.cc (create_temporary_var): Revert to only set context when in a function decl. gcc/testsuite/ChangeLog: * g++.dg/modules/pr114856.h: New test. * g++.dg/modules/pr114856_a.H: New test. * g++.dg/modules/pr114856_b.C: New test. Signed-off-by: Nathaniel Shead Reviewed-by: Jason Merrill Reviewed-by: Patrick Palka --- gcc/cp/call.cc | 3 +++ gcc/cp/init.cc | 2 +- gcc/testsuite/g++.dg/modules/pr114856.h | 12 ++++++++++++ gcc/testsuite/g++.dg/modules/pr114856_a.H | 5 +++++ gcc/testsuite/g++.dg/modules/pr114856_b.C | 5 +++++ 5 files changed, 26 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/modules/pr114856.h create mode 100644 gcc/testsuite/g++.dg/modules/pr114856_a.H create mode 100644 gcc/testsuite/g++.dg/modules/pr114856_b.C (limited to 'gcc') diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index 7c4ecf0..e058da7 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -13802,6 +13802,9 @@ make_temporary_var_for_ref_to_temp (tree decl, tree type) tree name = mangle_ref_init_variable (decl); DECL_NAME (var) = name; SET_DECL_ASSEMBLER_NAME (var, name); + + /* Set the context to make the variable mergeable in modules. */ + DECL_CONTEXT (var) = current_scope (); } else /* Create a new cleanup level if necessary. */ diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc index c1b5b74..7bb98f4 100644 --- a/gcc/cp/init.cc +++ b/gcc/cp/init.cc @@ -4287,7 +4287,7 @@ create_temporary_var (tree type) TREE_USED (decl) = 1; DECL_ARTIFICIAL (decl) = 1; DECL_IGNORED_P (decl) = 1; - DECL_CONTEXT (decl) = current_scope (); + DECL_CONTEXT (decl) = current_function_decl; return decl; } diff --git a/gcc/testsuite/g++.dg/modules/pr114856.h b/gcc/testsuite/g++.dg/modules/pr114856.h new file mode 100644 index 0000000..b1a3c2c --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/pr114856.h @@ -0,0 +1,12 @@ +// PR c++/114856 + +#include +struct A { + ~A(); +}; +struct V { + V(std::initializer_list); +}; +struct data { + V v{{}}; +}; diff --git a/gcc/testsuite/g++.dg/modules/pr114856_a.H b/gcc/testsuite/g++.dg/modules/pr114856_a.H new file mode 100644 index 0000000..6195277 --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/pr114856_a.H @@ -0,0 +1,5 @@ +// PR c++/114856 +// { dg-additional-options "-fmodule-header" } +// { dg-module-cmi {} } + +#include "pr114856.h" diff --git a/gcc/testsuite/g++.dg/modules/pr114856_b.C b/gcc/testsuite/g++.dg/modules/pr114856_b.C new file mode 100644 index 0000000..f81dc8b --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/pr114856_b.C @@ -0,0 +1,5 @@ +// PR c++/114856 +// { dg-additional-options "-fmodules-ts" } + +#include "pr114856.h" +import "pr114856_a.H"; -- cgit v1.1