A `BLOCK` statement opens a new scope. It is different from other scopes
in that implicitly typed entities are defined in the enclosing non-block
scope, not immediately in the block. This means that `IMPORT` statements
can cause them to be hidden.
Check that blocks can't have `IMPLICIT` statements in them. It is simpler
for the parser not to deal with the different between a
specification-part and a block-specification-part.
Change `ImplicitRules` to have a parent that is consulted when there isn't
an answer in the current one. For an interface body that does not happen
but for all other nested scopes it does. This parent link eliminates the
need for the `implicitRules_` stack. Make `isImplicitNoneType_` and
`isImplicitNoneExternal_` optional: not set means look in parent.
Fixesflang-compiler/f18#71.
Remove `CurrNonTypeScope()` and put the logic in `Symbol::FindSymbol`.
Original-commit: flang-compiler/f18@a153a2ee33
Reviewed-on: https://github.com/flang-compiler/f18/pull/169
Tree-same-pre-rewrite: false
In Symbol and Scope, use SourceName (== parser::CharBlock) in place of
Name (== std::string) so that names in the symtab have provenance. We
may ultimately have multiple source locations associated with a symbol.
ImplicitRules: Add isImplicitNoneType and isImplicitNoneExternal flags.
MessageHandler: Add methods to emit messages associated with source
locations.
Detect conflicting declarations of symbols (e.g. as subprogram and
variable).
Handle attribute statements like ASYNCHRONOUS statement: make sure the
symbol is present and set the attribute on it. Check that these all have
a type declared by the end of the specification part if IMPLICIT NONE.
Find variables named in Variable and Expr nodes and check they have
types declared if IMPLICIT NONE. Otherwise, make sure they are in the
symtab and apply the implicit type rules at the end of the scope.
Push a scope for MainProgram nodes and add a symbol for the name if it
has one.
Rename Scope::map_type to Scope::mapType
Add tests for errors currently being detected. There is no framework for
running them yet, just source files with the expected errors in
comments.
Original-commit: flang-compiler/f18@39e6fa4169
Reviewed-on: https://github.com/flang-compiler/f18/pull/49
Tree-same-pre-rewrite: false