Allow CFI_cdesc_t in argument lists with -fc-prototypes.

This patch fixes and reorganizes dumping C prototypes.  It makes the following
changes:

	- BIND(C) types are now always output before any global symbols
	- CFI_cdesc_t is issued for assumed shape and assumed rank arguments.
	- BIND(C,NAME="...") entities were not always issued.

gcc/fortran/ChangeLog:

	PR fortran/118359
	* dump-parse-tree.cc (show_external_symbol): New function.
	(write_type): Add prototype, put in restrictions on what not to dump.
	(has_cfi_cdesc): New function.
	(need_iso_fortran_binding): New function.
	(gfc_dump_c_prototypes): Adjust to take only a file output.  Add
	"#include <ISO_Fortran_binding.h" if CFI_cdesc_t is found.
	Traverse global namespaces to dump types and the globalsymol list
	to dump external symbols.
	(gfc_dump_external_c_prototypes): Traverse global namespaces.
	(get_c_type_name): Handle CFI_cdesc_t.
	(write_proc): Also pass array spec to get_c_type_name.
	* gfortran.h (gfc_dump_c_prototypes): Adjust prototype.
	* parse.cc (gfc_parse_file): Adjust call to gfc_dump_c_prototypes.

1 files changed, 134 insertions, 20 deletions

diff --git a/gcc/fortran/dump-parse-tree.cc b/gcc/fortran/dump-parse-tree.cc
index 0f983e9..0ae1350 100644
--- a/gcc/fortran/dump-parse-tree.cc
+++ b/gcc/fortran/dump-parse-tree.cc
@@ -4015,27 +4015,93 @@ gfc_dump_parse_tree (gfc_namespace *ns, FILE *file)
   show_namespace (ns);
 }
 
-/* This part writes BIND(C) definition for use in external C programs.  */
+/* This part writes BIND(C) prototypes and declatations, and prototypes
+   for EXTERNAL preocedures, for use in a C programs.  */
 
 static void write_interop_decl (gfc_symbol *);
 static void write_proc (gfc_symbol *, bool);
+static void show_external_symbol (gfc_gsymbol *, void *);
+static void write_type (gfc_symbol *sym);
+
+/* Do we need to write out an #include <ISO_Fortran_binding.h> or not?  */
+
+static void
+has_cfi_cdesc (gfc_gsymbol *gsym, void *p)
+{
+  bool *data_p = (bool *) p;
+  gfc_formal_arglist *f;
+  gfc_symbol *sym;
+
+  if (*data_p)
+    return;
+
+  if (gsym->ns == NULL || gsym->sym_name == NULL )
+    return;
+
+  gfc_find_symbol (gsym->sym_name, gsym->ns, 0, &sym);
+
+  if (sym == NULL || sym->attr.flavor != FL_PROCEDURE || !sym->attr.is_bind_c)
+    return;
+
+  for (f = sym->formal; f; f = f->next)
+    {
+      gfc_symbol *s;
+      s = f->sym;
+      if (s->as && (s->as->type == AS_ASSUMED_RANK || s->as->type == AS_ASSUMED_SHAPE))
+	{
+	  *data_p = true;
+	  return;
+	}
+    }
+}
+
+static bool
+need_iso_fortran_binding ()
+{
+  bool needs_include = false;
+
+  if (gfc_gsym_root == NULL)
+    return false;
+
+  gfc_traverse_gsymbol (gfc_gsym_root, has_cfi_cdesc, (void *) &needs_include);
+  return needs_include;
+}
 
 void
-gfc_dump_c_prototypes (gfc_namespace *ns, FILE *file)
+gfc_dump_c_prototypes (FILE *file)
 {
+  bool bind_c = true;
   int error_count;
+  gfc_namespace *ns;
   gfc_get_errors (NULL, &error_count);
   if (error_count != 0)
     return;
+
+  if (gfc_gsym_root == NULL)
+    return;
+
   dumpfile = file;
-  gfc_traverse_ns (ns, write_interop_decl);
+  if (need_iso_fortran_binding ())
+    fputs ("#include <ISO_Fortran_binding.h>\n\n", dumpfile);
+
+  for (ns = gfc_global_ns_list; ns; ns = ns->sibling)
+    gfc_traverse_ns (ns, write_type);
+
+  gfc_traverse_gsymbol (gfc_gsym_root, show_external_symbol, (void *) &bind_c);
 }
 
-/* Loop over all global symbols, writing out their declarations.  */
+/* Loop over all external symbols, writing out their declarations.  */
 
 void
 gfc_dump_external_c_prototypes (FILE * file)
 {
+  bool bind_c = false;
+  int error_count;
+
+  gfc_get_errors (NULL, &error_count);
+  if (error_count != 0)
+    return;
+
   dumpfile = file;
   fprintf (dumpfile,
 	   _("/* Prototypes for external procedures generated from %s\n"
@@ -4044,18 +4110,47 @@ gfc_dump_external_c_prototypes (FILE * file)
 	     "   BIND(C) feature of standard Fortran instead.  */\n\n"),
 	   gfc_source_file, pkgversion_string, version_string);
 
-  for (gfc_current_ns = gfc_global_ns_list; gfc_current_ns;
-       gfc_current_ns = gfc_current_ns->sibling)
-    {
-      gfc_symbol *sym = gfc_current_ns->proc_name;
+  if (gfc_gsym_root == NULL)
+    return;
 
-      if (sym == NULL || sym->attr.flavor != FL_PROCEDURE
-	  || sym->attr.is_bind_c)
-	continue;
+  gfc_traverse_gsymbol (gfc_gsym_root, show_external_symbol, (void *) &bind_c);
+}
+
+/* Callback function for dumping external symbols, be they BIND(C) or
+ external.  */
+
+static void
+show_external_symbol (gfc_gsymbol *gsym, void *data)
+{
+  bool bind_c, *data_p;
+  gfc_symbol *sym;
+  const char *name;
+
+  if (gsym->ns == NULL)
+    return;
+
+  name = gsym->sym_name ? gsym->sym_name : gsym->name;
+
+  gfc_find_symbol (name, gsym->ns, 0, &sym);
+  if (sym == NULL)
+    return;
+
+  data_p = (bool *) data;
+  bind_c = *data_p;
 
+  if (bind_c)
+    {
+      if (!sym->attr.is_bind_c)
+	return;
+
+      write_interop_decl (sym);
+    }
+  else
+    {
+      if (sym->attr.flavor != FL_PROCEDURE || sym->attr.is_bind_c)
+	return;
       write_proc (sym, false);
     }
-  return;
 }
 
 enum type_return { T_OK=0, T_WARN, T_ERROR };
@@ -4076,6 +4171,15 @@ get_c_type_name (gfc_typespec *ts, gfc_array_spec *as, const char **pre,
   *asterisk = false;
   *post = "";
   *type_name = "<error>";
+
+  if (as && (as->type == AS_ASSUMED_RANK || as->type == AS_ASSUMED_SHAPE))
+    {
+      *asterisk = true;
+      *post = "";
+      *type_name = "CFI_cdesc_t";
+      return T_OK;
+    }
+
   if (ts->type == BT_REAL || ts->type == BT_INTEGER || ts->type == BT_COMPLEX
       || ts->type == BT_UNSIGNED)
     {
@@ -4195,20 +4299,24 @@ get_c_type_name (gfc_typespec *ts, gfc_array_spec *as, const char **pre,
       ret = T_OK;
     }
 
-  if (ret != T_ERROR && as)
+  if (ret != T_ERROR && as && as->type == AS_EXPLICIT)
     {
       mpz_t sz;
       bool size_ok;
       size_ok = spec_size (as, &sz);
-      gcc_assert (size_ok == true);
-      gmp_snprintf (post_buffer, sizeof(post_buffer), "[%Zd]", sz);
-      *post = post_buffer;
-      mpz_clear (sz);
+      if (size_ok)
+	{
+	  gmp_snprintf (post_buffer, sizeof(post_buffer), "[%Zd]", sz);
+	  *post = post_buffer;
+	  mpz_clear (sz);
+	  *asterisk = false;
+	}
     }
   return ret;
 }
 
 /* Write out a declaration.  */
+
 static void
 write_decl (gfc_typespec *ts, gfc_array_spec *as, const char *sym_name,
 	    bool func_ret, locus *where, bool bind_c)
@@ -4247,6 +4355,11 @@ write_type (gfc_symbol *sym)
 {
   gfc_component *c;
 
+  /* Don't dump our iso c module.  */
+
+  if (sym->from_intmod == INTMOD_ISO_C_BINDING || sym->attr.flavor != FL_DERIVED)
+    return;
+
   fprintf (dumpfile, "typedef struct %s {\n", sym->name);
   for (c = sym->components; c; c = c->next)
     {
@@ -4255,7 +4368,7 @@ write_type (gfc_symbol *sym)
       fputs (";\n", dumpfile);
     }
 
-  fprintf (dumpfile, "} %s;\n", sym->name);
+  fprintf (dumpfile, "} %s;\n\n", sym->name);
 }
 
 /* Write out a variable.  */
@@ -4321,7 +4434,7 @@ write_proc (gfc_symbol *sym, bool bind_c)
     {
       gfc_symbol *s;
       s = f->sym;
-      rok = get_c_type_name (&(s->ts), NULL, &pre, &type_name, &asterisk,
+      rok = get_c_type_name (&(s->ts), s->as, &pre, &type_name, &asterisk,
 			     &post, false);
       if (rok == T_ERROR)
 	{
@@ -4332,7 +4445,8 @@ write_proc (gfc_symbol *sym, bool bind_c)
 	  return;
 	}
 
-      if (!s->attr.value)
+      /* For explicit arrays, we already set the asterisk above.  */
+      if (!s->attr.value && !(s->as && s->as->type == AS_EXPLICIT))
 	asterisk = true;
 
       if (s->attr.intent == INTENT_IN && !s->attr.value)