diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/fortran/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/fortran/gfc-internals.texi | 27 |
2 files changed, 31 insertions, 0 deletions
diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog index 3dcb424..ca29477 100644 --- a/gcc/fortran/ChangeLog +++ b/gcc/fortran/ChangeLog @@ -1,3 +1,7 @@ +2010-07-04 Daniel Kraft <d@domob.eu> + + * gfc-internals.texi (gfc_code): Document BLOCK and ASSOCIATE. + 2010-07-04 Paul Thomas <pault@gcc.gnu.org> PR fortran/44596 diff --git a/gcc/fortran/gfc-internals.texi b/gcc/fortran/gfc-internals.texi index 90f90fd..ed4c5ed 100644 --- a/gcc/fortran/gfc-internals.texi +++ b/gcc/fortran/gfc-internals.texi @@ -406,6 +406,33 @@ case-block, and @code{extx.case_list} contains the case-values this block corresponds to. The @code{block} member links to the next case in the list. +@subsection @code{BLOCK} and @code{ASSOCIATE} + +The code related to a @code{BLOCK} statement is stored inside an +@code{gfc_code} structure (say @var{c}) +with @code{c.op} set to @code{EXEC_BLOCK}. The +@code{gfc_namespace} holding the locally defined variables of the +@code{BLOCK} is stored in @code{c.ext.block.ns}. The code inside the +construct is in @code{c.code}. + +@code{ASSOCIATE} constructs are based on @code{BLOCK} and thus also have +the internal storage structure described above (including @code{EXEC_BLOCK}). +However, for them @code{c.ext.block.assoc} is set additionally and points +to a linked list of @code{gfc_association_list} structures. Those +structures basically store a link of associate-names to target expressions. +The associate-names themselves are still also added to the @code{BLOCK}'s +namespace as ordinary symbols, but they have their @code{gfc_symbol}'s +member @code{assoc} set also pointing to the association-list structure. +This way associate-names can be distinguished from ordinary variables +and their target expressions identified. + +For association to expressions (as opposed to variables), at the very beginning +of the @code{BLOCK} construct assignments are automatically generated to +set the corresponding variables to their target expressions' values, and +later on the compiler simply disallows using such associate-names in contexts +that may change the value. + + @c gfc_expr @c -------- |