| Message ID | 66f1fd8e.170a0220.2e1c55.07f2@mx.google.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++/modules: Implement P1815 "Translation-unit-local entities" | expand |
On 9/23/24 7:45 PM, Nathaniel Shead wrote: > Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk? > > -- >8 -- > > Currently the streaming code uses TREE_CONSTANT to determine whether an > entity will have a definition that is interesting to stream out. This > is not sufficient, however; we also need to write the definition of > references, since although not TREE_CONSTANT they can still be usable in > constant expressions. > > gcc/cp/ChangeLog: > > * module.cc (has_definition): Also write definition of > references initialized with a constant expression. > > gcc/testsuite/ChangeLog: > > * g++.dg/modules/cexpr-5_a.C: New test. > * g++.dg/modules/cexpr-5_b.C: New test. > > Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com> > --- > gcc/cp/module.cc | 6 +++++- > gcc/testsuite/g++.dg/modules/cexpr-5_a.C | 13 +++++++++++++ > gcc/testsuite/g++.dg/modules/cexpr-5_b.C | 9 +++++++++ > 3 files changed, 27 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/g++.dg/modules/cexpr-5_a.C > create mode 100644 gcc/testsuite/g++.dg/modules/cexpr-5_b.C > > diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc > index f5df9e875d3..7589de2348d 100644 > --- a/gcc/cp/module.cc > +++ b/gcc/cp/module.cc > @@ -11829,7 +11829,11 @@ has_definition (tree decl) > since there's no TU to emit them in otherwise. */ > return true; > > - if (!TREE_CONSTANT (decl)) > + if (!TREE_CONSTANT (decl) > + /* A reference is never TREE_CONSTANT, but still stream its > + definition if it's usable in constant expressions. */ > + && !(TYPE_REF_P (TREE_TYPE (decl)) > + && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))) Maybe this wants decl_{maybe_,}constant_var_p? OK either way. Jason
diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc index f5df9e875d3..7589de2348d 100644 --- a/gcc/cp/module.cc +++ b/gcc/cp/module.cc @@ -11829,7 +11829,11 @@ has_definition (tree decl) since there's no TU to emit them in otherwise. */ return true; - if (!TREE_CONSTANT (decl)) + if (!TREE_CONSTANT (decl) + /* A reference is never TREE_CONSTANT, but still stream its + definition if it's usable in constant expressions. */ + && !(TYPE_REF_P (TREE_TYPE (decl)) + && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))) return false; return true; diff --git a/gcc/testsuite/g++.dg/modules/cexpr-5_a.C b/gcc/testsuite/g++.dg/modules/cexpr-5_a.C new file mode 100644 index 00000000000..3a9f00523f6 --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/cexpr-5_a.C @@ -0,0 +1,13 @@ +// { dg-additional-options "-fmodules-ts" } +// { dg-module-cmi M } + +export module M; + +int x = 123; +void f() {} + +int& xr = x; +auto& fr = f; + +constexpr int& cxr = xr; +constexpr auto& cfr = fr; diff --git a/gcc/testsuite/g++.dg/modules/cexpr-5_b.C b/gcc/testsuite/g++.dg/modules/cexpr-5_b.C new file mode 100644 index 00000000000..4b1b901104b --- /dev/null +++ b/gcc/testsuite/g++.dg/modules/cexpr-5_b.C @@ -0,0 +1,9 @@ +// { dg-additional-options "-fmodules-ts" } + +module M; + +constexpr auto& use_xr = xr; +constexpr auto& use_fr = fr; + +static_assert(&cxr == &use_xr); +static_assert(&cfr == &use_fr);
Bootstrapped and regtested on x86_64-pc-linux-gnu, OK for trunk? -- >8 -- Currently the streaming code uses TREE_CONSTANT to determine whether an entity will have a definition that is interesting to stream out. This is not sufficient, however; we also need to write the definition of references, since although not TREE_CONSTANT they can still be usable in constant expressions. gcc/cp/ChangeLog: * module.cc (has_definition): Also write definition of references initialized with a constant expression. gcc/testsuite/ChangeLog: * g++.dg/modules/cexpr-5_a.C: New test. * g++.dg/modules/cexpr-5_b.C: New test. Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com> --- gcc/cp/module.cc | 6 +++++- gcc/testsuite/g++.dg/modules/cexpr-5_a.C | 13 +++++++++++++ gcc/testsuite/g++.dg/modules/cexpr-5_b.C | 9 +++++++++ 3 files changed, 27 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/modules/cexpr-5_a.C create mode 100644 gcc/testsuite/g++.dg/modules/cexpr-5_b.C