On September 5, 2017 11:16:53 PM GMT+02:00, Jakub Jelinek <ja...@redhat.com>
wrote:
>Hi!
>
>If a DECL_THREAD_LOCAL_P decl has NULL DECL_INITIAL and
>-fzero-initialized-in-bss (the default), we ICE starting with
>r251602, which changed bss_initializer_p:
>+ /* Do not put constants into the .bss section, they belong in a
>readonly
>+ section. */
>+ return (!TREE_READONLY (decl)
>+ &&
>to:
> (DECL_INITIAL (decl) == NULL
> /* In LTO we have no errors in program; error_mark_node is used
> to mark offlined constructors. */
> || (DECL_INITIAL (decl) == error_mark_node
> && !in_lto_p)
> || (flag_zero_initialized_in_bss
> && initializer_zerop (DECL_INITIAL (decl))))
>Previously because bss_initializer_p for these returned true, ret was
>SECCAT_BSS and therefore we set it to SECCAT_TBSS as intended, but now
>ret
>is not SECCAT_BSS, but as TLS has only tbss and tdata possibilities, we
>still want to use tbss. DECL_INITIAL NULL for a decl means implicit
>zero
>initialization.
>
>Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok
>for
>trunk?
OK.
Richard.
>2017-09-05 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/82095
> * varasm.c (categorize_decl_for_section): Use SECCAT_TBSS for TLS vars
>with
> NULL DECL_INITIAL.
>
> * gcc.dg/tls/pr82095.c: New test.
>
>--- gcc/varasm.c.jj 2017-09-01 18:43:29.000000000 +0200
>+++ gcc/varasm.c 2017-09-04 12:29:10.166564776 +0200
>@@ -6562,8 +6562,9 @@ categorize_decl_for_section (const_tree
> /* Note that this would be *just* SECCAT_BSS, except that there's
> no concept of a read-only thread-local-data section. */
> if (ret == SECCAT_BSS
>- || (flag_zero_initialized_in_bss
>- && initializer_zerop (DECL_INITIAL (decl))))
>+ || DECL_INITIAL (decl) == NULL
>+ || (flag_zero_initialized_in_bss
>+ && initializer_zerop (DECL_INITIAL (decl))))
> ret = SECCAT_TBSS;
> else
> ret = SECCAT_TDATA;
>--- gcc/testsuite/gcc.dg/tls/pr82095.c.jj 2017-09-04 12:44:16.650538220
>+0200
>+++ gcc/testsuite/gcc.dg/tls/pr82095.c 2017-09-04 12:44:08.000000000
>+0200
>@@ -0,0 +1,16 @@
>+/* PR middle-end/82095 */
>+/* { dg-do compile } */
>+/* { dg-options "-Og -fno-tree-ccp" } */
>+/* { dg-require-effective-target tls } */
>+/* { dg-add-options tls } */
>+
>+static int b;
>+static __thread int c;
>+
>+void
>+foo (void)
>+{
>+ if (b)
>+ if (c)
>+ b = 1;
>+}
>
> Jakub
