[PATCH 0/5] Implement Ada Pragma Import and Pragma Export

[PATCH 0/5] Implement Ada Pragma Import and Pragma Export

[Tom Tromey]

This adds better support to GDB for Ada's import and export feature.
There are some minor cleanups to start with, then the bulk of the
feature in the last patch, which I think should be reasonably
self-explanatory.

Regression tested on x86-64 Fedora 36.  It's also been running in the
AdaCore internal test suite for a while.

Tom

---
Tom Tromey (5):
      Introduce lookup_minimal_symbol_linkage
      Bump MAX_SYMBOL_IMPLS
      Define symbol::value_block separately
      Introduce symbol_block_ops::get_block_value
      Handle Ada Pragma Import and Pragma Export

 gdb/Makefile.in                          |   1 +
 gdb/dwarf2/ada-imported.c                | 122 +++++++++++++++++++++++++++++
 gdb/dwarf2/loc.h                         |   2 +
 gdb/dwarf2/read.c                        | 128 +++++++++++++++++++++++++++++++
 gdb/minsyms.c                            |  22 ++++++
 gdb/minsyms.h                            |   8 ++
 gdb/symtab.c                             |  36 +++------
 gdb/symtab.h                             |  20 ++++-
 gdb/testsuite/gdb.ada/complete.exp       |   2 +
 gdb/testsuite/gdb.ada/complete/pck.ads   |   4 +-
 gdb/testsuite/gdb.ada/import.exp         |  58 ++++++++++++++
 gdb/testsuite/gdb.ada/import/inc.c       |  27 +++++++
 gdb/testsuite/gdb.ada/import/pkg.adb     |  28 +++++++
 gdb/testsuite/gdb.ada/import/pkg.ads     |  33 ++++++++
 gdb/testsuite/gdb.ada/import/prog.adb    |  31 ++++++++
 gdb/testsuite/gdb.ada/info_auto_lang.exp |  10 ++-
 16 files changed, 499 insertions(+), 33 deletions(-)
---
base-commit: d0aa28e155baf16ec37afdf0193c3d58816c1927
change-id: 20230314-submit-pragma-import-export-c38bb4077953

Best regards,
-- 
Tom Tromey <tromey@adacore.com>

[PATCH 1/5] Introduce lookup_minimal_symbol_linkage

[Tom Tromey]

This introduces a new function, lookup_minimal_symbol_linkage, and
refactors a couple other existing functions to call it.  This function
will be used in a subsequent patch.
---
 gdb/minsyms.c | 22 ++++++++++++++++++++++
 gdb/minsyms.h |  8 ++++++++
 gdb/symtab.c  | 31 ++++++++-----------------------
 3 files changed, 38 insertions(+), 23 deletions(-)

diff --git a/gdb/minsyms.c b/gdb/minsyms.c
index 02e36cc6dd2..aed37978bb9 100644
--- a/gdb/minsyms.c
+++ b/gdb/minsyms.c
@@ -592,6 +592,28 @@ lookup_minimal_symbol_linkage (const char *name, struct objfile *objf)
 
 /* See minsyms.h.  */
 
+struct bound_minimal_symbol
+lookup_minimal_symbol_linkage (const char *name, bool only_main)
+{
+  for (objfile *objfile : current_program_space->objfiles ())
+    {
+      if (objfile->separate_debug_objfile_backlink != nullptr)
+	continue;
+
+      if (only_main && (objfile->flags & OBJF_MAINLINE) == 0)
+	continue;
+
+      bound_minimal_symbol minsym = lookup_minimal_symbol_linkage (name,
+								   objfile);
+      if (minsym.minsym != nullptr)
+	return minsym;
+    }
+
+  return {};
+}
+
+/* See minsyms.h.  */
+
 struct bound_minimal_symbol
 lookup_minimal_symbol_text (const char *name, struct objfile *objf)
 {
diff --git a/gdb/minsyms.h b/gdb/minsyms.h
index e9081495eb1..40513b148ff 100644
--- a/gdb/minsyms.h
+++ b/gdb/minsyms.h
@@ -236,6 +236,14 @@ extern struct bound_minimal_symbol lookup_minimal_symbol_linkage
   (const char *name, struct objfile *objf)
   ATTRIBUTE_NONNULL (1) ATTRIBUTE_NONNULL (2);
 
+/* A variant of lookup_minimal_symbol_linkage that iterates over all
+   objfiles.  If ONLY_MAIN is true, then only an objfile with
+   OBJF_MAINLINE will be considered.  */
+
+extern struct bound_minimal_symbol lookup_minimal_symbol_linkage
+  (const char *name, bool only_main)
+  ATTRIBUTE_NONNULL (1);
+
 /* Look through all the current minimal symbol tables and find the
    first minimal symbol that matches NAME and PC.  If OBJF is non-NULL,
    limit the search to that objfile.  Returns a pointer to the minimal
diff --git a/gdb/symtab.c b/gdb/symtab.c
index e11f9262a22..80395f99f24 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -6475,17 +6475,10 @@ get_symbol_address (const struct symbol *sym)
   gdb_assert (sym->aclass () == LOC_STATIC);
 
   const char *linkage_name = sym->linkage_name ();
-
-  for (objfile *objfile : current_program_space->objfiles ())
-    {
-      if (objfile->separate_debug_objfile_backlink != nullptr)
-	continue;
-
-      bound_minimal_symbol minsym
-	= lookup_minimal_symbol_linkage (linkage_name, objfile);
-      if (minsym.minsym != nullptr)
-	return minsym.value_address ();
-    }
+  bound_minimal_symbol minsym = lookup_minimal_symbol_linkage (linkage_name,
+							       false);
+  if (minsym.minsym != nullptr)
+    return minsym.value_address ();
   return sym->m_value.address;
 }
 
@@ -6498,18 +6491,10 @@ get_msymbol_address (struct objfile *objf, const struct minimal_symbol *minsym)
   gdb_assert ((objf->flags & OBJF_MAINLINE) == 0);
 
   const char *linkage_name = minsym->linkage_name ();
-
-  for (objfile *objfile : current_program_space->objfiles ())
-    {
-      if (objfile->separate_debug_objfile_backlink == nullptr
-	  && (objfile->flags & OBJF_MAINLINE) != 0)
-	{
-	  bound_minimal_symbol found
-	    = lookup_minimal_symbol_linkage (linkage_name, objfile);
-	  if (found.minsym != nullptr)
-	    return found.value_address ();
-	}
-    }
+  bound_minimal_symbol found = lookup_minimal_symbol_linkage (linkage_name,
+							      true);
+  if (found.minsym != nullptr)
+    return found.value_address ();
   return (minsym->m_value.address
 	  + objf->section_offsets[minsym->section_index ()]);
 }

-- 
2.39.1

[PATCH 2/5] Bump MAX_SYMBOL_IMPLS

[Tom Tromey]

A subsequent patch will introduce more aclass registrations, causing
the number to go over the current maximum.  This bumps the number.
Note that there's a separate static assert that ensures that this
number doesn't get too large for the field size in the symbol.
---
 gdb/symtab.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 80395f99f24..57ba61c2c05 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -6330,7 +6330,7 @@ static int next_aclass_value = LOC_FINAL_VALUE;
 
 /* The maximum number of "aclass" registrations we support.  This is
    constant for convenience.  */
-#define MAX_SYMBOL_IMPLS (LOC_FINAL_VALUE + 10)
+#define MAX_SYMBOL_IMPLS (LOC_FINAL_VALUE + 11)
 
 /* The objects representing the various "aclass" values.  The elements
    from 0 up to LOC_FINAL_VALUE-1 represent themselves, and subsequent

-- 
2.39.1

[PATCH 3/5] Define symbol::value_block separately

[Tom Tromey]

This moves the definition of symbol::value_block outside of the class.
A subsequent patch will change this method to use SYMBOL_BLOCK_OPS,
and it seemed simplest to move this method out-of-line, and cleaner to
do this as a separate change.
---
 gdb/symtab.h | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/gdb/symtab.h b/gdb/symtab.h
index 005b64b5a08..0a42fd2380c 100644
--- a/gdb/symtab.h
+++ b/gdb/symtab.h
@@ -1346,10 +1346,7 @@ struct symbol : public general_symbol_info, public allocate_on_obstack
     m_value.common_block = common_block;
   }
 
-  const block *value_block () const
-  {
-    return m_value.block;
-  }
+  const block *value_block () const;
 
   void set_value_block (const block *block)
   {
@@ -1507,6 +1504,12 @@ struct block_symbol
 #define SYMBOL_REGISTER_OPS(symbol)	((symbol)->impl ().ops_register)
 #define SYMBOL_LOCATION_BATON(symbol)   (symbol)->aux_value
 
+inline const block *
+symbol::value_block () const
+{
+  return m_value.block;
+}
+
 extern int register_symbol_computed_impl (enum address_class,
 					  const struct symbol_computed_ops *);
 

-- 
2.39.1

[PATCH 4/5] Introduce symbol_block_ops::get_block_value

[Tom Tromey]

This adds a new callback to symbol_block_ops.  This callback lets a
LOC_BLOCK symbol implement its own function to find the underlying
block.
---
 gdb/symtab.c | 3 ++-
 gdb/symtab.h | 9 +++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 57ba61c2c05..237b3ff794f 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -6391,7 +6391,8 @@ register_symbol_block_impl (enum address_class aclass,
 
   /* Sanity check OPS.  */
   gdb_assert (ops != NULL);
-  gdb_assert (ops->find_frame_base_location != NULL);
+  gdb_assert (ops->find_frame_base_location != nullptr
+	      || ops->get_block_value != nullptr);
 
   return result;
 }
diff --git a/gdb/symtab.h b/gdb/symtab.h
index 0a42fd2380c..ea3cf395f26 100644
--- a/gdb/symtab.h
+++ b/gdb/symtab.h
@@ -1149,6 +1149,12 @@ struct symbol_block_ops
      the corresponding DW_AT_frame_base attribute.  */
   CORE_ADDR (*get_frame_base) (struct symbol *framefunc,
 			       frame_info_ptr frame);
+
+  /* Return the block for this function.  So far, this is used to
+     implement function aliases.  So, if this is set, then it's not
+     necessary to set the other functions in this structure; and vice
+     versa.  */
+  const block *(*get_block_value) (const struct symbol *sym);
 };
 
 /* Functions used with LOC_REGISTER and LOC_REGPARM_ADDR.  */
@@ -1507,6 +1513,9 @@ struct block_symbol
 inline const block *
 symbol::value_block () const
 {
+  if (SYMBOL_BLOCK_OPS (this) != nullptr
+      && SYMBOL_BLOCK_OPS (this)->get_block_value != nullptr)
+    return SYMBOL_BLOCK_OPS (this)->get_block_value (this);
   return m_value.block;
 }
 

-- 
2.39.1

[PATCH 5/5] Handle Ada Pragma Import and Pragma Export

[Tom Tromey]

Ada can import C APIs and also export Ada constructs to C via Pragma
Import and Pragma Export.  This patch adds support for these to gdb,
by arranging to either defer some aspects of a symbol to the
underlying C symbol (for Import) or by introducing a second symbol
(for Export).  A somewhat tricky approach is needed, both because gdb
doesn't generally handle symbol aliasing, and because Ada treats
symbol names in an unusual way (as compared to the rest of gdb).
---
 gdb/Makefile.in                          |   1 +
 gdb/dwarf2/ada-imported.c                | 122 +++++++++++++++++++++++++++++
 gdb/dwarf2/loc.h                         |   2 +
 gdb/dwarf2/read.c                        | 128 +++++++++++++++++++++++++++++++
 gdb/testsuite/gdb.ada/complete.exp       |   2 +
 gdb/testsuite/gdb.ada/complete/pck.ads   |   4 +-
 gdb/testsuite/gdb.ada/import.exp         |  58 ++++++++++++++
 gdb/testsuite/gdb.ada/import/inc.c       |  27 +++++++
 gdb/testsuite/gdb.ada/import/pkg.adb     |  28 +++++++
 gdb/testsuite/gdb.ada/import/pkg.ads     |  33 ++++++++
 gdb/testsuite/gdb.ada/import/prog.adb    |  31 ++++++++
 gdb/testsuite/gdb.ada/info_auto_lang.exp |  10 ++-
 12 files changed, 442 insertions(+), 4 deletions(-)

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 40497541880..a8d665ef5a6 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -1062,6 +1062,7 @@ COMMON_SFILES = \
 	dummy-frame.c \
 	dwarf2/abbrev.c \
 	dwarf2/abbrev-cache.c \
+	dwarf2/ada-imported.c \
 	dwarf2/attribute.c \
 	dwarf2/comp-unit-head.c \
 	dwarf2/cooked-index.c \
diff --git a/gdb/dwarf2/ada-imported.c b/gdb/dwarf2/ada-imported.c
new file mode 100644
index 00000000000..d1d99be6923
--- /dev/null
+++ b/gdb/dwarf2/ada-imported.c
@@ -0,0 +1,122 @@
+/* Ada Pragma Import support.
+
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "symtab.h"
+#include "value.h"
+#include "dwarf2/loc.h"
+
+/* Helper to get the imported symbol's real name.  */
+static const char *
+get_imported_name (const struct symbol *sym)
+{
+  return (const char *) SYMBOL_LOCATION_BATON (sym);
+}
+
+/* Implement the read_variable method from symbol_computed_ops.  */
+
+static struct value *
+ada_imported_read_variable (struct symbol *symbol, frame_info_ptr frame)
+{
+  const char *name = get_imported_name (symbol);
+  bound_minimal_symbol minsym = lookup_minimal_symbol_linkage (name, false);
+  if (minsym.minsym == nullptr)
+    error (_("could not find imported name %s"), name);
+  return value_at (symbol->type (), minsym.value_address ());
+}
+
+/* Implement the read_variable method from symbol_computed_ops.  */
+
+static enum symbol_needs_kind
+ada_imported_get_symbol_read_needs (struct symbol *symbol)
+{
+  return SYMBOL_NEEDS_NONE;
+}
+
+/* Implement the describe_location method from
+   symbol_computed_ops.  */
+
+static void
+ada_imported_describe_location (struct symbol *symbol, CORE_ADDR addr,
+				struct ui_file *stream)
+{
+  gdb_printf (stream, "an imported name for '%s'",
+	      get_imported_name (symbol));
+}
+
+/* Implement the tracepoint_var_ref method from
+   symbol_computed_ops.  */
+
+static void
+ada_imported_tracepoint_var_ref (struct symbol *symbol, struct agent_expr *ax,
+				 struct axs_value *value)
+{
+  /* Probably could be done, but not needed right now.  */
+  error (_("not implemented: trace of imported Ada symbol"));
+}
+
+/* Implement the generate_c_location method from
+   symbol_computed_ops.  */
+
+static void
+ada_imported_generate_c_location (struct symbol *symbol, string_file *stream,
+				  struct gdbarch *gdbarch,
+				  std::vector<bool> &registers_used,
+				  CORE_ADDR pc, const char *result_name)
+{
+  /* Probably could be done, but not needed right now, and perhaps not
+     ever.  */
+  error (_("not implemented: compile translation of imported Ada symbol"));
+}
+
+const struct symbol_computed_ops ada_imported_funcs =
+{
+  ada_imported_read_variable,
+  nullptr,
+  ada_imported_get_symbol_read_needs,
+  ada_imported_describe_location,
+  0,
+  ada_imported_tracepoint_var_ref,
+  ada_imported_generate_c_location
+};
+
+/* Implement the get_block_value method from symbol_block_ops.  */
+
+static const block *
+ada_alias_get_block_value (const struct symbol *sym)
+{
+  const char *name = get_imported_name (sym);
+  block_symbol real_symbol = lookup_global_symbol (name, nullptr,
+						   VAR_DOMAIN);
+  if (real_symbol.symbol == nullptr)
+    error (_("could not find alias '%s' for function '%s'"),
+	   name, sym->print_name ());
+  if (real_symbol.symbol->aclass () != LOC_BLOCK)
+    error (_("alias '%s' for function '%s' is not a function"),
+	   name, sym->print_name ());
+
+  return real_symbol.symbol->value_block ();
+}
+
+const struct symbol_block_ops ada_function_alias_funcs =
+{
+  nullptr,
+  nullptr,
+  ada_alias_get_block_value
+};
diff --git a/gdb/dwarf2/loc.h b/gdb/dwarf2/loc.h
index ad60177e93c..1fec834787b 100644
--- a/gdb/dwarf2/loc.h
+++ b/gdb/dwarf2/loc.h
@@ -246,9 +246,11 @@ struct dwarf2_property_baton
 
 extern const struct symbol_computed_ops dwarf2_locexpr_funcs;
 extern const struct symbol_computed_ops dwarf2_loclist_funcs;
+extern const struct symbol_computed_ops ada_imported_funcs;
 
 extern const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs;
 extern const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs;
+extern const struct symbol_block_ops ada_function_alias_funcs;
 
 /* Determined tail calls for constructing virtual tail call frames.  */
 
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 138537cfefd..a47f7f61b51 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -142,8 +142,10 @@ static const registry<objfile>::key<dwarf2_per_bfd>
 
 static int dwarf2_locexpr_index;
 static int dwarf2_loclist_index;
+static int ada_imported_index;
 static int dwarf2_locexpr_block_index;
 static int dwarf2_loclist_block_index;
+static int ada_block_index;
 
 /* Size of .debug_loclists section header for 32-bit DWARF format.  */
 #define LOCLIST_HEADER_SIZE32 12
@@ -1072,6 +1074,9 @@ static void queue_comp_unit (dwarf2_per_cu_data *per_cu,
 
 static void process_queue (dwarf2_per_objfile *per_objfile);
 
+static bool is_ada_import_or_export (dwarf2_cu *cu, const char *name,
+				     const char *linkagename);
+
 /* Class, the destructor of which frees all allocated queue entries.  This
    will only have work to do if an error was thrown while processing the
    dwarf.  If no error was thrown then the queue entries should have all
@@ -9993,6 +9998,31 @@ inherit_abstract_dies (struct die_info *die, struct dwarf2_cu *cu)
     compute_delayed_physnames (origin_cu);
 }
 
+/* A helper to handle Ada's "Pragma Import" feature when it is applied
+   to a function.  */
+
+static bool
+check_ada_pragma_import (struct die_info *die, struct dwarf2_cu *cu)
+{
+  /* A Pragma Import will have both a name and a linkage name.  */
+  const char *name = dwarf2_name (die, cu);
+  if (name == nullptr)
+    return false;
+
+  const char *linkage_name = dw2_linkage_name (die, cu);
+  /* Disallow the special Ada symbols.  */
+  if (!is_ada_import_or_export (cu, name, linkage_name))
+    return false;
+
+  /* A Pragma Import will be a declaration, while a Pragma Export will
+     not be.  */
+  if (!die_is_declaration (die, cu))
+    return false;
+
+  new_symbol (die, read_type_die (die, cu), cu);
+  return true;
+}
+
 static void
 read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
 {
@@ -10039,6 +10069,14 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
       return;
     }
 
+  if (check_ada_pragma_import (die, cu))
+    {
+      /* We already made the symbol for the Pragma Import, and because
+	 it is a declaration, we know it won't have any other
+	 important information, so we can simply return.  */
+      return;
+    }
+
   /* Ignore functions with missing or invalid low and high pc attributes.  */
   if (dwarf2_get_pc_bounds (die, &lowpc, &highpc, cu, nullptr, nullptr)
       <= PC_BOUNDS_INVALID)
@@ -18751,6 +18789,51 @@ var_decode_location (struct attribute *attr, struct symbol *sym,
     cu->has_loclist = true;
 }
 
+/* A helper function to add an "export" symbol.  The new symbol starts
+   as a clone of ORIG, but is modified to defer to the symbol named
+   ORIG_NAME.  The original symbol uses the name given in the source
+   code, and the symbol that is created here uses the linkage name as
+   its name.  See ada-imported.c.  */
+
+static void
+add_ada_export_symbol (struct symbol *orig, const char *new_name,
+		       const char *orig_name, struct dwarf2_cu *cu,
+		       struct pending **list_to_add)
+{
+  struct symbol *copy
+    = new (&cu->per_objfile->objfile->objfile_obstack) symbol (*orig);
+  copy->set_linkage_name (new_name);
+  SYMBOL_LOCATION_BATON (copy) = (void *) orig_name;
+  copy->set_aclass_index (copy->aclass () == LOC_BLOCK
+			  ? ada_block_index
+			  : ada_imported_index);
+  add_symbol_to_list (copy, list_to_add);
+}
+
+/* A helper function that decides if a given symbol is an Ada Pragma
+   Import or Pragma Export.  */
+
+static bool
+is_ada_import_or_export (dwarf2_cu *cu, const char *name,
+			 const char *linkagename)
+{
+  return (cu->lang () == language_ada
+	  && linkagename != nullptr
+	  && !streq (name, linkagename)
+	  /* The following exclusions are necessary because symbols
+	     with names or linkage names that match here will meet the
+	     other criteria but are not in fact caused by Pragma
+	     Import or Pragma Export, and applying the import/export
+	     treatment to them will introduce problems.  Some of these
+	     checks only apply to functions, but it is simpler and
+	     harmless to always do them all.  */
+	  && !startswith (name, "__builtin")
+	  && !startswith (linkagename, "___ghost_")
+	  && !startswith (linkagename, "__gnat")
+	  && !startswith (linkagename, "_ada_")
+	  && !streq (linkagename, "adainit"));
+}
+
 /* Given a pointer to a DWARF information entry, figure out if we need
    to make a symbol table entry for it, and if so, create a new entry
    and return a pointer to it.
@@ -18891,6 +18974,28 @@ new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
 	    {
 	      list_to_add = cu->list_in_scope;
 	    }
+
+	  if (is_ada_import_or_export (cu, name, linkagename))
+	    {
+	      /* This is either a Pragma Import or Export.  They can
+		 be distinguished by the declaration flag.  */
+	      sym->set_linkage_name (name);
+	      if (die_is_declaration (die, cu))
+		{
+		  /* For Import, create a symbol using the source
+		     name, and have it refer to the linkage name.  */
+		  SYMBOL_LOCATION_BATON (sym) = (void *) linkagename;
+		  sym->set_aclass_index (ada_block_index);
+		}
+	      else
+		{
+		  /* For Export, create a symbol using the source
+		     name, then create a second symbol that refers
+		     back to it.  */
+		  add_ada_export_symbol (sym, linkagename, name, cu,
+					 list_to_add);
+		}
+	    }
 	  break;
 	case DW_TAG_inlined_subroutine:
 	  /* SYMBOL_BLOCK_VALUE (sym) will be filled in later by
@@ -18983,6 +19088,15 @@ new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
 		}
 	      else
 		list_to_add = cu->list_in_scope;
+
+	      if (is_ada_import_or_export (cu, name, linkagename))
+		{
+		  /* This is a Pragma Export.  A Pragma Import won't
+		     be seen here, because it will not have a location
+		     and so will be handled below.  */
+		  add_ada_export_symbol (sym, name, linkagename, cu,
+					 list_to_add);
+		}
 	    }
 	  else
 	    {
@@ -19004,6 +19118,16 @@ new_symbol (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
 		  if (!suppress_add)
 		    list_to_add = cu->list_in_scope;
 		}
+	      else if (is_ada_import_or_export (cu, name, linkagename))
+		{
+		  /* This is a Pragma Import.  A Pragma Export won't
+		     be seen here, because it will have a location and
+		     so will be handled above.  */
+		  sym->set_linkage_name (name);
+		  list_to_add = cu->list_in_scope;
+		  SYMBOL_LOCATION_BATON (sym) = (void *) linkagename;
+		  sym->set_aclass_index (ada_imported_index);
+		}
 	      else if (attr2 != nullptr && attr2->as_boolean ()
 		       && dwarf2_attr (die, DW_AT_type, cu) != NULL)
 		{
@@ -21935,11 +22059,15 @@ the demangler."),
 							&dwarf2_locexpr_funcs);
   dwarf2_loclist_index = register_symbol_computed_impl (LOC_COMPUTED,
 							&dwarf2_loclist_funcs);
+  ada_imported_index = register_symbol_computed_impl (LOC_COMPUTED,
+						      &ada_imported_funcs);
 
   dwarf2_locexpr_block_index = register_symbol_block_impl (LOC_BLOCK,
 					&dwarf2_block_frame_base_locexpr_funcs);
   dwarf2_loclist_block_index = register_symbol_block_impl (LOC_BLOCK,
 					&dwarf2_block_frame_base_loclist_funcs);
+  ada_block_index = register_symbol_block_impl (LOC_BLOCK,
+						&ada_function_alias_funcs);
 
 #if GDB_SELF_TEST
   selftests::register_test ("dw2_expand_symtabs_matching",
diff --git a/gdb/testsuite/gdb.ada/complete.exp b/gdb/testsuite/gdb.ada/complete.exp
index 57b65466012..9e9250545e9 100644
--- a/gdb/testsuite/gdb.ada/complete.exp
+++ b/gdb/testsuite/gdb.ada/complete.exp
@@ -160,6 +160,7 @@ test_gdb_complete "pck" \
                               "p pck.ambiguous_func" \
                               "p pck.external_identical_one" \
                               "p pck.inner.inside_variable" \
+			      "p pck.internal_capitalized" \
                               "p pck.local_identical_one" \
                               "p pck.local_identical_two" \
                               "p pck.my_global_variable" \
@@ -172,6 +173,7 @@ test_gdb_complete "pck." \
                               "p pck.ambiguous_func" \
                               "p pck.external_identical_one" \
                               "p pck.inner.inside_variable" \
+			      "p pck.internal_capitalized" \
                               "p pck.local_identical_one" \
                               "p pck.local_identical_two" \
                               "p pck.my_global_variable" \
diff --git a/gdb/testsuite/gdb.ada/complete/pck.ads b/gdb/testsuite/gdb.ada/complete/pck.ads
index 77f89678fae..034c142d91d 100644
--- a/gdb/testsuite/gdb.ada/complete/pck.ads
+++ b/gdb/testsuite/gdb.ada/complete/pck.ads
@@ -17,8 +17,8 @@ package Pck is
 
    My_Global_Variable : Integer := 1;
 
-   Exported_Capitalized : Integer := 2;
-   pragma Export (C, Exported_Capitalized, "Exported_Capitalized");
+   Internal_Capitalized : Integer := 2;
+   pragma Export (C, Internal_Capitalized, "Exported_Capitalized");
 
    Local_Identical_One : Integer := 4;
    Local_Identical_Two : Integer := 8;
diff --git a/gdb/testsuite/gdb.ada/import.exp b/gdb/testsuite/gdb.ada/import.exp
new file mode 100644
index 00000000000..866b431aac5
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/import.exp
@@ -0,0 +1,58 @@
+# Copyright 2023 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib "ada.exp"
+
+require allow_ada_tests
+
+standard_ada_testfile prog
+
+set cfile "inc"
+set csrcfile ${srcdir}/${subdir}/${testdir}/${cfile}.c
+set cobject [standard_output_file ${cfile}.o]
+
+if {[gdb_compile "${csrcfile}" "${cobject}" object debug] != ""} {
+    untested "could not compile C file"
+    return
+}
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable \
+	 [list debug additional_flags=-largs \
+	      additional_flags=${cobject} additional_flags=-margs]] != ""} {
+    return -1
+}
+
+clean_restart ${testfile}
+
+set bp_location [gdb_get_line_number "BREAK" ${testdir}/prog.adb]
+runto "prog.adb:$bp_location"
+
+gdb_test "print ordinary_var" " = 78"
+
+gdb_test "print imported_var" " = 42"
+gdb_test "print imported_var_ada" " = 42"
+gdb_test "print local_imported_var" " = 42"
+gdb_test "print pkg.imported_var_ada" " = 42"
+
+gdb_test "print pkg.exported_var_ada" " = 99"
+gdb_test "print exported_var_ada" " = 99"
+
+gdb_breakpoint "pkg.imported_func_ada" message
+gdb_breakpoint "imported_func" message
+gdb_breakpoint "imported_func_ada" message
+
+gdb_breakpoint "local_imported_func" message
+gdb_breakpoint "pkg.exported_func_ada" message
+gdb_breakpoint "exported_func_ada" message
+gdb_breakpoint "exported_func" message
diff --git a/gdb/testsuite/gdb.ada/import/inc.c b/gdb/testsuite/gdb.ada/import/inc.c
new file mode 100644
index 00000000000..c3a1ea18d55
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/import/inc.c
@@ -0,0 +1,27 @@
+/* Copyright 2023 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+extern int exported_var;
+extern int exported_func (void);
+
+int imported_var = 42;
+
+int
+imported_func (void)
+{
+  return exported_var + exported_func ();
+}
diff --git a/gdb/testsuite/gdb.ada/import/pkg.adb b/gdb/testsuite/gdb.ada/import/pkg.adb
new file mode 100644
index 00000000000..e4f1c1a88b7
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/import/pkg.adb
@@ -0,0 +1,28 @@
+--  Copyright 2023 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package body Pkg is
+
+   function Exported_Func_Ada return Integer is
+   begin
+      return Imported_Var_Ada;
+   end Exported_Func_Ada;
+
+   procedure Do_Nothing (A : System.Address) is
+   begin
+      null;
+   end Do_Nothing;
+
+end Pkg;
diff --git a/gdb/testsuite/gdb.ada/import/pkg.ads b/gdb/testsuite/gdb.ada/import/pkg.ads
new file mode 100644
index 00000000000..5576d1b92d7
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/import/pkg.ads
@@ -0,0 +1,33 @@
+--  Copyright 2023 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+with System;
+package Pkg is
+
+   Imported_Var_Ada : Integer;
+   pragma Import (C, Imported_Var_Ada, "imported_var");
+
+   function Imported_Func_Ada return Integer;
+   pragma Import (C, Imported_Func_Ada, "imported_func");
+
+   Exported_Var_Ada : Integer := 99;
+   pragma Export (C, Exported_Var_Ada, "exported_var");
+
+   function Exported_Func_Ada return Integer;
+   pragma Export (C, Exported_Func_Ada, "exported_func");
+
+   procedure Do_Nothing (A : System.Address);
+
+end Pkg;
diff --git a/gdb/testsuite/gdb.ada/import/prog.adb b/gdb/testsuite/gdb.ada/import/prog.adb
new file mode 100644
index 00000000000..77f2073a633
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/import/prog.adb
@@ -0,0 +1,31 @@
+--  Copyright 2023 Free Software Foundation, Inc.
+--
+--  This program is free software; you can redistribute it and/or modify
+--  it under the terms of the GNU General Public License as published by
+--  the Free Software Foundation; either version 3 of the License, or
+--  (at your option) any later version.
+--
+--  This program is distributed in the hope that it will be useful,
+--  but WITHOUT ANY WARRANTY; without even the implied warranty of
+--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+--  GNU General Public License for more details.
+--
+--  You should have received a copy of the GNU General Public License
+--  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+with Pkg;
+
+procedure Prog is
+   Ordinary_Var : Integer := 78;
+
+   Local_Imported_Var : Integer;
+   pragma Import (C, Local_Imported_Var, "imported_var");
+
+   function Local_Imported_Func return Integer;
+   pragma Import (C, Local_Imported_Func, "imported_func");
+begin
+   Local_Imported_Var := Local_Imported_Func;  --  BREAK
+   Pkg.Imported_Var_Ada := Pkg.Imported_Func_Ada;
+   Pkg.Do_Nothing (Pkg.Imported_Func_Ada'Address);
+   Pkg.Do_Nothing (Pkg.Exported_Func_Ada'Address);
+end Prog;
diff --git a/gdb/testsuite/gdb.ada/info_auto_lang.exp b/gdb/testsuite/gdb.ada/info_auto_lang.exp
index 5202605b731..5134643c0ca 100644
--- a/gdb/testsuite/gdb.ada/info_auto_lang.exp
+++ b/gdb/testsuite/gdb.ada/info_auto_lang.exp
@@ -51,8 +51,14 @@ if {![runto "some_c.c:$bp_location"]} {
 
 set func_in_c(c_syntax)      "${decimal}:	void proc_in_c\\\(void\\\);"
 set func_in_c(ada_syntax)    "${decimal}:	procedure proc_in_c;"
-set func_in_ada(c_syntax)    "${decimal}:	void proc_in_ada\\\(void\\\);"
-set func_in_ada(ada_syntax)  "${decimal}:	procedure proc_in_ada;"
+set func_in_ada(c_syntax) \
+    [string cat \
+	 "${decimal}:	void proc_in_ada\\\(void\\\);\r\n" \
+	 "${decimal}:	void proc_in_ada.something_in_c\\\(void\\\);"]
+set func_in_ada(ada_syntax) \
+    [string cat \
+	 "${decimal}:	procedure proc_in_ada;\r\n" \
+	 "${decimal}:	procedure proc_in_ada.something_in_c;"]
 
 set type_in_c(c_syntax) "${decimal}:	typedef struct {\\.\\.\\.} some_type_in_c;"
 set type_in_c(ada_syntax) [multi_line \

-- 
2.39.1

Re: [PATCH 0/5] Implement Ada Pragma Import and Pragma Export

[Tom Tromey]

>>>>> "Tom" == Tom Tromey via Gdb-patches <gdb-patches@sourceware.org> writes:

Tom> This adds better support to GDB for Ada's import and export feature.
Tom> There are some minor cleanups to start with, then the bulk of the
Tom> feature in the last patch, which I think should be reasonably
Tom> self-explanatory.

Tom> Regression tested on x86-64 Fedora 36.  It's also been running in the
Tom> AdaCore internal test suite for a while.

Another AdaCore employee found a problem when debugging the GNAT front
end that I think was caused by this series, so I'm going to hold off
checking it in until that is found & fixed.

Tom