[flang] Compile the output of -fdebug-unparse-with-modules (#135696)
The output of a compilation with the -fdebug-unparse-with-modules option
comprises its normal unparsed output along with the regenerated contents
of any modules that were required from module files. This is handy for
producing stand-alone test cases.
The modules' contents are generated by the same code that writes module
files, so they can contain some USE associations to private entities in
other modules that are necessary to complete local declarations, usually
initializers. Such USE associations to private entities are not flagged
as fatal errors when modules are read from module files, but they
currently are caught when the output produced by this option is being
read back in to the compiler.
Handle this case by softening the error to a warning when one module
uses a private entity from another with an alias containing the
non-conforming '$' character. (I could have omitted the message
altogether, but there are other valid warnings that will occur due to
undefined function result variables; further, I didn't want to provide a
general hole around the protection of private names.)
diff --git a/flang/docs/ModFiles.md b/flang/docs/ModFiles.md
index cde2e42..dd0ade5 100644
--- a/flang/docs/ModFiles.md
+++ b/flang/docs/ModFiles.md
@@ -98,7 +98,14 @@
are represented in the module file with `USE` statements.
Name aliases are sometimes necessary when an entity from another
module is needed for a declaration and conflicts with another
-entity of the same name.
+entity of the same name, or is `PRIVATE`.
+These aliases have currency symbols (`$`) in them.
+When a module
+is parsed from a module file, no error is emitted for associating
+such an alias with a `PRIVATE` name.
+A module parsed from another source file that is not a module file
+(notably, the output of the `-fdebug-unparse-with-modules` option)
+will emit only warnings.
## Reading and writing module files
diff --git a/flang/lib/Semantics/resolve-names.cpp b/flang/lib/Semantics/resolve-names.cpp
index 74367b5..7ec6252 100644
--- a/flang/lib/Semantics/resolve-names.cpp
+++ b/flang/lib/Semantics/resolve-names.cpp
@@ -3325,9 +3325,19 @@
// Privacy is not enforced in module files so that generic interfaces
// can be resolved to private specific procedures in specification
// expressions.
- Say(useName, "'%s' is PRIVATE in '%s'"_err_en_US, MakeOpName(useName),
- useModuleScope_->GetName().value());
- return {};
+ // Local names that contain currency symbols ('$') are created by the
+ // module file writer when a private name in another module is needed to
+ // process a local declaration. These can show up in the output of
+ // -fdebug-unparse-with-modules, too, so go easy on them.
+ if (currScope().IsModule() &&
+ localName.ToString().find("$") != std::string::npos) {
+ Say(useName, "'%s' is PRIVATE in '%s'"_warn_en_US, MakeOpName(useName),
+ useModuleScope_->GetName().value());
+ } else {
+ Say(useName, "'%s' is PRIVATE in '%s'"_err_en_US, MakeOpName(useName),
+ useModuleScope_->GetName().value());
+ return {};
+ }
}
auto &localSymbol{MakeSymbol(localName)};
DoAddUse(useName, localName, localSymbol, *useSymbol);
diff --git a/flang/test/Semantics/resolve11.f90 b/flang/test/Semantics/resolve11.f90
index db508f0..39a30b8 100644
--- a/flang/test/Semantics/resolve11.f90
+++ b/flang/test/Semantics/resolve11.f90
@@ -86,3 +86,17 @@
use m5, only: foo, fun
print *, fun() ! ok
end
+
+module m6
+ !WARNING: 'foo' is PRIVATE in 'm5'
+ use m5, only: name$with$dollar => foo
+ !ERROR: 'foo' is PRIVATE in 'm5'
+ use m5, only: normal_name => foo
+end
+
+subroutine s6
+ !The special dispensation for USE association of private names to local
+ !aliases with '$' in them only applies to modules.
+ !ERROR: 'foo' is PRIVATE in 'm5'
+ use m5, only: name$with$dollar => foo
+end
