Merge pull request #550 from svaarala/fix-opt-packed-tval-handling

Fix feature option defaults when already provided

RELEASES.rst

@@ -1381,6 +1381,10 @@ Planned
   exotic pointer models by avoiding arithmetic and binary operations on
   (u)intptr_t values (GH-530, GH-539)
 
+* Fix a genconfig legacy feature option bug in Duktape 1.4.0 which caused
+  DUK_USE_PACKED_TVAL to default to false unless forced using
+  DUK_OPT_PACKED_TVAL (GH-550)
+
 2.0.0 (XXXX-XX-XX)
 ------------------
 

config/config-options/DUK_USE_ALIGN_BY.yaml

@@ -1,5 +1,4 @@
 define: DUK_USE_ALIGN_BY
-# FIXME: resolve wrapper
 feature_snippet: |
   #if !defined(DUK_USE_ALIGN_BY)
   #if defined(DUK_OPT_FORCE_ALIGN)
@@ -8,6 +7,7 @@ feature_snippet: |
   #define DUK_USE_ALIGN_BY 8
   #endif
   #endif
+feature_no_default: true  # provided by architecture unless forced
 introduced: 1.3.0
 default: 8
 tags:

config/config-options/DUK_USE_EXAMPLE.yaml

@@ -30,6 +30,12 @@ related_feature_defines:
 #   #endif
 #   #endif
 
+# Feature default value is provided by platform, compiler, or architecture.
+# DUK_OPT_xxx handling can force the value if explicitly requested by
+# DUK_OPT_XXX or DUK_OPT_NO_xxx, but if neither is given, don't emit a
+# default.
+#feature_no_default: true
+
 # Duktape version number where this option was first introduced.
 introduced: 1.1.0
 

config/config-options/DUK_USE_PACKED_TVAL.yaml

@@ -1,9 +1,6 @@
 define: DUK_USE_PACKED_TVAL
 feature_enables: DUK_OPT_PACKED_TVAL
-# FIXME: current snippet is actually:
-#if defined(DUK_USE_PACKED_TVAL_POSSIBLE) && !defined(DUK_OPT_NO_PACKED_TVAL)
-#define DUK_USE_PACKED_TVAL
-#endif
+feature_no_default: true  # provided by architecture unless forced
 introduced: 1.0.0
 default: false
 tags:

config/config-options/DUK_USE_SETJMP.yaml

@@ -1,5 +1,6 @@
 define: DUK_USE_SETJMP
 feature_enables: DUK_OPT_SETJMP
+feature_no_default: true  # provided by platform unless forced
 introduced: 1.1.0
 default: true
 tags:

config/config-options/DUK_USE_SIGSETJMP.yaml

@@ -1,5 +1,6 @@
 define: DUK_USE_SIGSETJMP
 feature_enables: DUK_OPT_SIGSETJMP
+feature_no_default: true  # provided by platform unless forced
 introduced: 1.1.0
 default: false
 tags:

config/config-options/DUK_USE_UNDERSCORE_SETJMP.yaml

@@ -1,5 +1,6 @@
 define: DUK_USE_UNDERSCORE_SETJMP
 feature_enables: DUK_OPT_UNDERSCORE_SETJMP
+feature_no_default: true  # provided by platform unless forced
 introduced: 1.1.0
 default: false
 tags:

config/genconfig.py

@@ -927,7 +927,7 @@ def add_override_defines_section(opts, ret):
 
 # Add automatic DUK_OPT_XXX and DUK_OPT_NO_XXX handling for backwards
 # compatibility with Duktape 1.2 and before.
-def add_feature_option_handling(opts, ret, forced_opts):
+def add_feature_option_handling(opts, ret, forced_opts, already_provided_keys):
 	ret.chdr_block_heading('Feature option handling')
 
 	for doc in get_use_defs(removed=False, deprecated=False, unused=False):
@@ -962,7 +962,18 @@ def add_feature_option_handling(opts, ret, forced_opts):
 				ret.line('#undef %s' % config_define)
 			ret.line('#else')
 			undef_done = False
-			emit_default_from_config_meta(ret, doc, forced_opts, undef_done)
+
+			# For some options like DUK_OPT_PACKED_TVAL the default comes
+			# from platform definition.
+			if doc.get('feature_no_default', False):
+				print('Skip default for option %s' % config_define)
+				ret.line('/* Already provided above */')
+			elif already_provided_keys.has_key(config_define):
+				# This is a fallback in case config option metadata is wrong.
+				print('Skip default for option %s (already provided but not flagged in metadata!)' % config_define)
+				ret.line('/* Already provided above */')
+			else:
+				emit_default_from_config_meta(ret, doc, forced_opts, undef_done)
 			ret.line('#endif')
 		elif doc.has_key('feature_snippet'):
 			ret.lines(doc['feature_snippet'])
@@ -1294,7 +1305,8 @@ def generate_duk_config_header(opts, meta_dir):
 	# Automatic DUK_OPT_xxx feature option handling
 	if opts.support_feature_options:
 		print('Autogenerating feature option (DUK_OPT_xxx) support')
-		add_feature_option_handling(opts, ret, forced_opts)
+		tmp = Snippet(ret.join().split('\n'))
+		add_feature_option_handling(opts, ret, forced_opts, tmp.provides)
 
 	# Emit forced options.  If a corresponding option is already defined
 	# by a snippet above, #undef it first.