The code would only remove a variable from a common block if it was just
defined in the previous statement. The PR showed a case where a pre-existing
variable was put in the common block. When it was not removed, the common
block list was wrong and segfaulted (or infinite looped) when used later on.
I changed it so it would remove a variable from a common block if it was just
defined, or if it previously existed and was put in the common block in the
last statement.
This patch works with the example given in the PR and has no regressions in the
testsuite.
tested i686/linux.
--bud davis
2013-03-06 Bud Davis <jmda...@link.com>
PR fortran/59746
* symbol.c (gfc_restore_last_undo_checkpoint): Delete a common block
symbol if it was put in the list.
Index: gcc/gcc/testsuite/gfortran.dg/pr59746.f90
===================================================================
--- gcc/gcc/testsuite/gfortran.dg/pr59746.f90 (revision 0)
+++ gcc/gcc/testsuite/gfortran.dg/pr59746.f90 (revision 0)
@@ -0,0 +1,18 @@
+! { dg-do compile }
+!pr59746
+ CALL RCCFL(NVE,IR,NU3,VE(1,1,1,I))
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+! the PR only contained the two above.
+! success is no segfaults or infinite loops.
+! let's check some combinations
+ CALL ABC (INTG)
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ CALL DEF (NT1)
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ CALL GHI (NRESL)
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ COMMON /CCFILE/ INTG,NT1,NT2,NT3,NVM,NVE,NFRLE,NRESF,NRESL !{ dg-error
"Unexpected COMMON" }
+ END
Index: gcc/gcc/fortran/symbol.c
===================================================================
--- gcc/gcc/fortran/symbol.c (revision 208437)
+++ gcc/gcc/fortran/symbol.c (working copy)
@@ -3069,9 +3069,9 @@
FOR_EACH_VEC_ELT (latest_undo_chgset->syms, i, p)
{
- if (p->gfc_new)
+ if (p->gfc_new || (p->attr.in_common && !p->old_symbol->attr.in_common) )
{
- /* Symbol was new. */
+ /* Symbol was new. Or was old and just put in common */
if (p->attr.in_common && p->common_block && p->common_block->head)
{
/* If the symbol was added to any common block, it
@@ -3115,6 +3115,9 @@
/* The derived type is saved in the symtree with the first
letter capitalized; the all lower-case version to the
derived type contains its associated generic function. */
+ }
+ if (p->gfc_new)
+ {
if (p->attr.flavor == FL_DERIVED)
gfc_delete_symtree (&p->ns->sym_root, gfc_get_string ("%c%s",
(char) TOUPPER ((unsigned char) p->name[0]),
@@ -3125,7 +3128,9 @@
gfc_release_symbol (p);
}
else
- restore_old_symbol (p);
+ {
+ restore_old_symbol (p);
+ }
}
latest_undo_chgset->syms.truncate (0);
