Hi Tobias,
> > The problem occurs because GFC_MAX_MANGLED_SYMBOL_LEN is set to
> > GFC_MAX_SYMBOL_LEN*2+4, which is sufficient for a module name plus
> > function name (plus the additional "_"'s that get prepended), but
> > insufficient if a submodule name is included. The name then gets
> > truncated and can lead to two different functions having the same
> > (truncated) symbol name.
> >
> > The fix is to increase this length to GFC_MAX_SYMBOL_LEN*3+5 - which
> > allows for the submodule name plus the "." added between module and
> > submodule names.
> >
> > I've attached a patch for this which includes a new test case for this PR.
> > The patch regression tests cleanly.
> >
> > OK to commit?
>
> Can you also update the comment before the #define? It currently has:
>
> /* Mangled symbols take the form __module__name. */
> -#define GFC_MAX_MANGLED_SYMBOL_LEN (GFC_MAX_SYMBOL_LEN*2+4)
> +#define GFC_MAX_MANGLED_SYMBOL_LEN (GFC_MAX_SYMBOL_LEN*3+5)
Thanks for the suggestion. An updated patch is attached.
> PS: I wonder whether there are relevant systems which will fail because they
> do not handle that long symbol names...
Good question. Should I hold off on committing the patch until this can be
tested further? Or should I just go ahead and commit and deal with any such
problems if they show up?
Also, Richard Biener raised the question (in the PR) of whether this patch
would be an ABI change. I can see that it probably would be, but don't know
for sure. If it would change the ABI is there anything else that I need to
include in the patch?
Thanks,
Andrew
--
* Andrew Benson: http://users.obs.carnegiescience.edu/abenson/contact.html
* Galacticus: https://github.com/galacticusorg/galacticus
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index 52bc045..69171f3 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -23,8 +23,8 @@ along with GCC; see the file COPYING3. If not see
#include "predict.h" /* For enum br_predictor and PRED_*. */
-/* Mangled symbols take the form __module__name. */
-#define GFC_MAX_MANGLED_SYMBOL_LEN (GFC_MAX_SYMBOL_LEN*2+4)
+/* Mangled symbols take the form __module__name or __module.submodule__name. */
+#define GFC_MAX_MANGLED_SYMBOL_LEN (GFC_MAX_SYMBOL_LEN*3+5)
/* Struct for holding a block of statements. It should be treated as an
opaque entity and not modified directly. This allows us to change the
diff --git a/gcc/testsuite/gfortran.dg/pr93461.f90 b/gcc/testsuite/gfortran.dg/pr93461.f90
new file mode 100644
index 0000000..3bef326
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr93461.f90
@@ -0,0 +1,22 @@
+! { dg-do compile }
+! PR fortran/93461
+module aModuleWithAnAllowedName
+ interface
+ module subroutine aShortName()
+ end subroutine aShortName
+ end interface
+end module aModuleWithAnAllowedName
+
+submodule (aModuleWithAnAllowedName) aSubmoduleWithAVeryVeryVeryLongButEntirelyLegalName
+contains
+ subroutine aShortName()
+ call aSubroutineWithAVeryLongNameThatWillCauseAProblem()
+ call aSubroutineWithAVeryLongNameThatWillCauseAProblemAlso()
+ end subroutine aShortName
+
+ subroutine aSubroutineWithAVeryLongNameThatWillCauseAProblem()
+ end subroutine aSubroutineWithAVeryLongNameThatWillCauseAProblem
+
+ subroutine aSubroutineWithAVeryLongNameThatWillCauseAProblemAlso()
+ end subroutine aSubroutineWithAVeryLongNameThatWillCauseAProblemAlso
+end submodule aSubmoduleWithAVeryVeryVeryLongButEntirelyLegalName
2020-01-28 Andrew Benson <abenso...@gmail.com>
PR fortran/93461
* trans.h: Increase GFC_MAX_MANGLED_SYMBOL_LEN to
GFC_MAX_SYMBOL_LEN*3+5 to allow for inclusion of submodule name,
plus the "." between module and submodule names.
* gfortran.dg/pr93461.f90: New test.
