Thread-local variables with DECL_COMMON trigger an internal compiler
error on targets that use emulated TLS without register_common, when
we attempt to expand a call to the NULL register_common, with
testcases as simple as gcc.dg/tls/emutls-2.c.
The documentation states that, on such targets, common variables would
fall back to explicitly initialized. This patch rearranges the code
that deals with initialization of common and non-common variables,
complementing code that is already in place to detect
register_common-less targets.
Regstrapped on x86_64-linux-gnu, tested on an affected target.
Ok to install?
for gcc/ChangeLog
* tree-emutls.c (new_emutls_decl, emutls_common_1): Complete
handling of register_common-less targets.
for gcc/testsuite/ChangeLog
* gcc.dg/tls/emutls-3.c: New, combining emutls-2.c and
thr-init-2.c into an execution test with explicitly common
variables.
---
testsuite/gcc.dg/tls/emutls-3.c | 26 ++++++++++++++++++++++++++
tree-emutls.c | 4 ++--
2 files changed, 28 insertions(+), 2 deletions(-)
create mode 100644 testsuite/gcc.dg/tls/emutls-3.c
diff --git gcc/testsuite/gcc.dg/tls/emutls-3.c
gcc/testsuite/gcc.dg/tls/emutls-3.c
new file mode 100644
index 00000000..e062ba8
--- /dev/null
+++ gcc/testsuite/gcc.dg/tls/emutls-3.c
@@ -0,0 +1,26 @@
+/* { dg-do run } */
+/* { dg-require-effective-target tls } */
+/* { dg-require-effective-target global_constructor } */
+/* { dg-options "-O2" } */
+/* { dg-require-effective-target tls_runtime } */
+/* { dg-add-options tls } */
+
+__thread int i __attribute__((common));
+
+extern void abort (void);
+
+int test_code(int b)
+{
+ i += b ;
+ return i;
+}
+
+int main (int ac, char *av[])
+{
+ int a = test_code(test_code(1));
+
+ if ((a != 2) || (i != 2))
+ abort () ;
+
+ return 0;
+}
diff --git gcc/tree-emutls.c gcc/tree-emutls.c
index e924124..44755dd4 100644
--- gcc/tree-emutls.c
+++ gcc/tree-emutls.c
@@ -322,7 +322,7 @@ new_emutls_decl (tree decl, tree alias_of)
control structure with size and alignment information. Initialization
of COMMON block variables happens elsewhere via a constructor. */
if (!DECL_EXTERNAL (to)
- && (!DECL_COMMON (to)
+ && (!DECL_COMMON (to) || !targetm.emutls.register_common
|| (DECL_INITIAL (decl)
&& DECL_INITIAL (decl) != error_mark_node)))
{
@@ -360,7 +360,7 @@ emutls_common_1 (tree tls_decl, tree control_decl, tree
*pstmts)
tree x;
tree word_type_node;
- if (! DECL_COMMON (tls_decl)
+ if (!DECL_COMMON (tls_decl) || !targetm.emutls.register_common
|| (DECL_INITIAL (tls_decl)
&& DECL_INITIAL (tls_decl) != error_mark_node))
return;
--
Alexandre Oliva, freedom fighter he/him https://FSFLA.org/blogs/lxo
Free Software Evangelist Stallman was right, but he's left :(
GNU Toolchain Engineer FSMatrix: It was he who freed the first of us
FSF & FSFLA board member The Savior shall return (true);
