From dd9d14f7d53de07beff06004922a2bff20ece671 Mon Sep 17 00:00:00 2001
From: Nathaniel Shead <nathanieloshead@gmail.com>
Date: Wed, 14 Feb 2024 12:26:03 +1100
Subject: [PATCH] c++: Defer emitting inline variables [PR113708]
Inline variables are vague-linkage, and may or may not need to be
emitted in any TU that they are part of, similarly to e.g. template
instantiations.
Currently 'import_export_decl' assumes that inline variables have
already been emitted when it comes to end-of-TU processing, and so
crashes when importing non-trivially-initialised variables from a
module, as they have not yet been finalised.
This patch fixes this by ensuring that inline variables are always
deferred till end-of-TU processing, unifying the behaviour for module
and non-module code.
PR c++/113708
gcc/cp/ChangeLog:
* decl.cc (make_rtl_for_nonlocal_decl): Defer inline variables.
* decl2.cc (import_export_decl): Support inline variables.
gcc/testsuite/ChangeLog:
* g++.dg/debug/dwarf2/inline-var-1.C: Reference 'a' to ensure it
is emitted.
* g++.dg/debug/dwarf2/inline-var-3.C: Likewise.
* g++.dg/modules/init-7_a.H: New test.
* g++.dg/modules/init-7_b.C: New test.
Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
---
gcc/cp/decl.cc | 4 ++++
gcc/cp/decl2.cc | 7 +++++--
gcc/testsuite/g++.dg/debug/dwarf2/inline-var-1.C | 2 ++
gcc/testsuite/g++.dg/debug/dwarf2/inline-var-3.C | 2 ++
gcc/testsuite/g++.dg/modules/init-7_a.H | 6 ++++++
gcc/testsuite/g++.dg/modules/init-7_b.C | 6 ++++++
6 files changed, 25 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/modules/init-7_a.H
create mode 100644 gcc/testsuite/g++.dg/modules/init-7_b.C
diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index d19d09adde43..e47f694e4e56 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -7954,6 +7954,10 @@ make_rtl_for_nonlocal_decl (tree decl, tree init, const char* asmspec)
&& DECL_IMPLICIT_INSTANTIATION (decl))
defer_p = 1;
+ /* Defer vague-linkage variables. */
+ if (DECL_INLINE_VAR_P (decl))
+ defer_p = 1;
+
/* If we're not deferring, go ahead and assemble the variable. */
if (!defer_p)
rest_of_decl_compilation (decl, toplev, at_eof);
diff --git a/gcc/cp/decl2.cc b/gcc/cp/decl2.cc
index f569d4045ecc..1dddbaab38b0 100644
--- a/gcc/cp/decl2.cc
+++ b/gcc/cp/decl2.cc
@@ -3360,7 +3360,9 @@ import_export_decl (tree decl)
* implicit instantiations of function templates
- * inline function
+ * inline functions
+
+ * inline variables
* implicit instantiations of static data members of class
templates
@@ -3383,6 +3385,7 @@ import_export_decl (tree decl)
|| DECL_DECLARED_INLINE_P (decl));
else
gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
+ || DECL_INLINE_VAR_P (decl)
|| DECL_VTABLE_OR_VTT_P (decl)
|| DECL_TINFO_P (decl));
/* Check that a definition of DECL is available in this translation
@@ -3511,7 +3514,7 @@ import_export_decl (tree decl)
this entity as undefined in this translation unit. */
import_p = true;
}
- else if (DECL_FUNCTION_MEMBER_P (decl))
+ else if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FUNCTION_MEMBER_P (decl))
{
if (!DECL_DECLARED_INLINE_P (decl))
{
diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-1.C b/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-1.C
index 85f74a91521f..7ec20afc065c 100644
--- a/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-1.C
+++ b/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-1.C
@@ -8,6 +8,8 @@
// { dg-final { scan-assembler-times " DW_AT_\[^\n\r]*linkage_name" 7 } }
inline int a;
+int& ar = a;
+
struct S
{
static inline double b = 4.0;
diff --git a/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-3.C b/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-3.C
index 6345b5e2ec84..bb40a2295512 100644
--- a/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-3.C
+++ b/gcc/testsuite/g++.dg/debug/dwarf2/inline-var-3.C
@@ -11,6 +11,8 @@
// { dg-final { scan-assembler-times " DW_AT_\[^\n\r]*linkage_name" 7 } }
inline int a;
+int& ar = a;
+
struct S
{
static inline double b = 4.0;
diff --git a/gcc/testsuite/g++.dg/modules/init-7_a.H b/gcc/testsuite/g++.dg/modules/init-7_a.H
new file mode 100644
index 000000000000..7a0bb721c307
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/init-7_a.H
@@ -0,0 +1,6 @@
+// PR c++/113708
+// { dg-additional-options "-fmodule-header" }
+// { dg-module-cmi {} }
+
+inline int f() { return 42; }
+inline int a = f();
diff --git a/gcc/testsuite/g++.dg/modules/init-7_b.C b/gcc/testsuite/g++.dg/modules/init-7_b.C
new file mode 100644
index 000000000000..58bb0620ca51
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/init-7_b.C
@@ -0,0 +1,6 @@
+// PR c++/113708
+// { dg-module-do link }
+// { dg-additional-options "-fmodules-ts" }
+
+import "init-7_a.H";
+int main() { a; }
--
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