Print void types correctly in Rust

[deliverable/binutils-gdb.git] / gdb / rust-lang.c

diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c
index 0e9c62cddfd4390f989a0ada687b25d3e016d0a3..23ddd5aecda7d62dfd0822d122456bed31f3502c 100644 (file)
--- a/gdb/rust-lang.c
+++ b/gdb/rust-lang.c
@@ -147,15 +147,15 @@ rust_get_disr_info (struct type *type, const gdb_byte *valaddr,
          field is zero.  */
       while ((token = strsep (&tail, "$")) != NULL)
         {
-           if (sscanf (token, "%lu", &fieldno) != 1)
-             {
-                /* We have reached the enum name,
-                   which cannot start with a digit.  */
-                break;
-             }
+         if (sscanf (token, "%lu", &fieldno) != 1)
+           {
+             /* We have reached the enum name, which cannot start
+                with a digit.  */
+             break;
+           }
           if (fieldno >= TYPE_NFIELDS (member_type))
-      error (_("%s refers to field after end of member type"),
-             RUST_ENUM_PREFIX);
+           error (_("%s refers to field after end of member type"),
+                  RUST_ENUM_PREFIX);
 
           embedded_offset += TYPE_FIELD_BITPOS (member_type, fieldno) / 8;
           member_type = TYPE_FIELD_TYPE (member_type, fieldno);
@@ -163,10 +163,7 @@ rust_get_disr_info (struct type *type, const gdb_byte *valaddr,
 
       if (token >= name + strlen (TYPE_FIELD_NAME (type, 0)))
        error (_("Invalid form for %s"), RUST_ENUM_PREFIX);
-        value = unpack_long (member_type,
-                             valaddr + embedded_offset);
-      
-
+      value = unpack_long (member_type, valaddr + embedded_offset);
 
       if (value == 0)
        {
@@ -449,7 +446,7 @@ static const struct generic_val_print_decorations rust_decorations =
   " * I",
   "true",
   "false",
-  "void",
+  "()",
   "[",
   "]"
 };
@@ -732,13 +729,22 @@ rust_print_type (struct type *type, const char *varstring,
   if (show <= 0
       && TYPE_NAME (type) != NULL)
     {
-      fputs_filtered (TYPE_NAME (type), stream);
+      /* Rust calls the unit type "void" in its debuginfo,
+         but we don't want to print it as that.  */
+      if (TYPE_CODE (type) == TYPE_CODE_VOID)
+        fputs_filtered ("()", stream);
+      else
+        fputs_filtered (TYPE_NAME (type), stream);
       return;
     }
 
   type = check_typedef (type);
   switch (TYPE_CODE (type))
     {
+    case TYPE_CODE_VOID:
+      fputs_filtered ("()", stream);
+      break;
+
     case TYPE_CODE_FUNC:
       /* Delegate varargs to the C printer.  */
       if (TYPE_VARARGS (type))
@@ -756,8 +762,13 @@ rust_print_type (struct type *type, const char *varstring,
          rust_print_type (TYPE_FIELD_TYPE (type, i), "", stream, -1, 0,
                           flags);
        }
-      fputs_filtered (") -> ", stream);
-      rust_print_type (TYPE_TARGET_TYPE (type), "", stream, -1, 0, flags);
+      fputs_filtered (")", stream);
+      /* If it returns unit, we can omit the return type.  */
+      if (TYPE_CODE (TYPE_TARGET_TYPE (type)) != TYPE_CODE_VOID)
+        {
+          fputs_filtered (" -> ", stream);
+          rust_print_type (TYPE_TARGET_TYPE (type), "", stream, -1, 0, flags);
+        }
       break;
 
     case TYPE_CODE_ARRAY:
@@ -879,16 +890,17 @@ rust_print_type (struct type *type, const char *varstring,
          }
        fputs_filtered ("{\n", stream);
 
-  if (strncmp (TYPE_FIELD_NAME (type, 0), RUST_ENUM_PREFIX,
-       strlen (RUST_ENUM_PREFIX)) == 0) {
-    const char *zero_field = strrchr (TYPE_FIELD_NAME (type, 0), '$');
-    if (zero_field != NULL && strlen (zero_field) > 1)
-      {
-        fprintfi_filtered (level + 2, stream, "%s,\n", zero_field+1);
-        /* There is no explicit discriminant field, skip nothing.  */
-        skip_to = 0;
-      }
-  }
+       if (strncmp (TYPE_FIELD_NAME (type, 0), RUST_ENUM_PREFIX,
+                    strlen (RUST_ENUM_PREFIX)) == 0)
+         {
+           const char *zero_field = strrchr (TYPE_FIELD_NAME (type, 0), '$');
+           if (zero_field != NULL && strlen (zero_field) > 1)
+             {
+               fprintfi_filtered (level + 2, stream, "%s,\n", zero_field + 1);
+               /* There is no explicit discriminant field, skip nothing.  */
+               skip_to = 0;
+             }
+         }
 
        for (i = 0; i < TYPE_NFIELDS (type); ++i)
          {