Allow disabling RTTI/exceptions for android builds; disable by default on Android

Summary:
For fbandroid builds only, disable RTTI and exceptions by default.

Changelog: [Internal]

Reviewed By: philIip

Differential Revision: D31632757

fbshipit-source-id: cfe0e43486df19fcaacc2b5b818b9d00ec2d427f

Author: JoshuaGross

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/BUCK

@@ -11,8 +11,8 @@ rn_xplat_cxx_library(
         ],
         prefix = "react/fabric",
     ),
-    compiler_flags_enable_exceptions = True,
-    compiler_flags_enable_rtti = True,  # dynamic_cast used within Binding.cpp
+    compiler_flags_enable_exceptions = False,
+    compiler_flags_enable_rtti = False,  # for YogaLayoutableShadowNode?
     fbandroid_allow_jni_merging = True,
     labels = ["supermodule:xplat/default/public.react_native.infra"],
     platforms = ANDROID,

ReactCommon/react/config/BUCK

@@ -18,6 +18,8 @@ rn_xplat_cxx_library(
         ],
         prefix = "react/config",
     ),
+    compiler_flags_enable_exceptions = True,
+    compiler_flags_enable_rtti = True,  # for ReactNativeConfig
     fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
     fbobjc_preprocessor_flags = get_preprocessor_flags_for_build_mode() + get_apple_inspector_flags(),
     force_static = True,

ReactCommon/react/renderer/components/view/BUCK

@@ -35,6 +35,8 @@ rn_xplat_cxx_library(
         ],
         prefix = "react/renderer/components/view",
     ),
+    compiler_flags_enable_exceptions = False,
+    compiler_flags_enable_rtti = False,  # YogaLayoutableShadowNode
     fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
     fbobjc_preprocessor_flags = get_preprocessor_flags_for_build_mode() + get_apple_inspector_flags(),
     force_static = True,

ReactCommon/react/renderer/core/BUCK

@@ -32,8 +32,8 @@ rn_xplat_cxx_library(
         ],
         prefix = "react/renderer/core",
     ),
-    compiler_flags_enable_exceptions = True,
-    compiler_flags_enable_rtti = True,  # Needed for DebugStringConvertible - need to find a non-RTTI way to do this / enable RTTI for debug builds only
+    compiler_flags_enable_exceptions = False,
+    compiler_flags_enable_rtti = False,  # Needed for DebugStringConvertible - need to find a non-RTTI way to do this / enable RTTI for debug builds only. Also EventBeat/AsyncEventBeat
     fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
     fbobjc_preprocessor_flags = get_preprocessor_flags_for_build_mode() + get_apple_inspector_flags(),
     force_static = True,

ReactCommon/react/renderer/core/LayoutableShadowNode.cpp

@@ -17,6 +17,19 @@
 namespace facebook {
 namespace react {
 
+LayoutableShadowNode::LayoutableShadowNode(
+    ShadowNodeFragment const &fragment,
+    ShadowNodeFamily::Shared const &family,
+    ShadowNodeTraits traits)
+    : ShadowNode(fragment, family, traits), layoutMetrics_({}) {}
+
+LayoutableShadowNode::LayoutableShadowNode(
+    ShadowNode const &sourceShadowNode,
+    ShadowNodeFragment const &fragment)
+    : ShadowNode(sourceShadowNode, fragment),
+      layoutMetrics_(static_cast<LayoutableShadowNode const &>(sourceShadowNode)
+                         .layoutMetrics_) {}
+
 LayoutMetrics LayoutableShadowNode::computeRelativeLayoutMetrics(
     ShadowNodeFamily const &descendantNodeFamily,
     LayoutableShadowNode const &ancestorNode,
@@ -118,19 +131,6 @@ LayoutMetrics LayoutableShadowNode::computeRelativeLayoutMetrics(
   return layoutMetrics;
 }
 
-LayoutableShadowNode::LayoutableShadowNode(
-    ShadowNodeFragment const &fragment,
-    ShadowNodeFamily::Shared const &family,
-    ShadowNodeTraits traits)
-    : ShadowNode(fragment, family, traits), layoutMetrics_({}) {}
-
-LayoutableShadowNode::LayoutableShadowNode(
-    ShadowNode const &sourceShadowNode,
-    ShadowNodeFragment const &fragment)
-    : ShadowNode(sourceShadowNode, fragment),
-      layoutMetrics_(static_cast<LayoutableShadowNode const &>(sourceShadowNode)
-                         .layoutMetrics_) {}
-
 ShadowNodeTraits LayoutableShadowNode::BaseTraits() {
   auto traits = ShadowNodeTraits{};
   traits.set(ShadowNodeTraits::Trait::LayoutableKind);
@@ -202,16 +202,6 @@ Float LayoutableShadowNode::lastBaseline(Size size) const {
   return 0;
 }
 
-void LayoutableShadowNode::layoutTree(
-    LayoutContext layoutContext,
-    LayoutConstraints layoutConstraints) {
-  // Default implementation does nothing.
-}
-
-void LayoutableShadowNode::layout(LayoutContext layoutContext) {
-  // Default implementation does nothing.
-}
-
 ShadowNode::Shared LayoutableShadowNode::findNodeAtPoint(
     ShadowNode::Shared node,
     Point point) {

ReactCommon/react/renderer/core/LayoutableShadowNode.h

@@ -70,7 +70,7 @@ class LayoutableShadowNode : public ShadowNode {
    */
   virtual void layoutTree(
       LayoutContext layoutContext,
-      LayoutConstraints layoutConstraints);
+      LayoutConstraints layoutConstraints)=0;
 
   /*
    * Measures the node (and node content, probably recursively) with
@@ -101,7 +101,7 @@ class LayoutableShadowNode : public ShadowNode {
    * - Calculate and assign `LayoutMetrics` for the children;
    * - Call itself recursively on every child if needed.
    */
-  virtual void layout(LayoutContext layoutContext);
+  virtual void layout(LayoutContext layoutContext)=0;
 
   /*
    * Returns layout metrics computed during previous layout pass.

ReactCommon/react/renderer/debug/BUCK

@@ -31,6 +31,8 @@ rn_xplat_cxx_library(
         ],
         prefix = "react/renderer/debug",
     ),
+    compiler_flags_enable_exceptions = True,
+    compiler_flags_enable_rtti = True,  # DebugStringConvertible
     fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
     fbobjc_preprocessor_flags = get_preprocessor_flags_for_build_mode() + get_apple_inspector_flags(),
     force_static = True,

tools/build_defs/oss/rn_defs.bzl

@@ -80,7 +80,7 @@ def get_react_native_preprocessor_flags():
     return []
 
 # Building is not supported in OSS right now
-def rn_xplat_cxx_library(name, compiler_flags_enable_exceptions = True, compiler_flags_enable_rtti = True, **kwargs):
+def rn_xplat_cxx_library(name, compiler_flags_enable_exceptions = False, compiler_flags_enable_rtti = False, **kwargs):
     visibility = kwargs.get("visibility", [])
     kwargs = {
         k: v
@@ -97,17 +97,31 @@ def rn_xplat_cxx_library(name, compiler_flags_enable_exceptions = True, compiler
     # or being overridden in compiler_flags, it's very likely that the flag is set
     # app-wide or that we're otherwise in some special mode.
     kwargs["compiler_flags"] = kwargs.get("compiler_flags", [])
+    kwargs["fbobjc_compiler_flags"] = kwargs.get("fbobjc_compiler_flags", [])
+    kwargs["fbandroid_compiler_flags"] = kwargs.get("fbandroid_compiler_flags", [])
+    kwargs["windows_compiler_flags"] = kwargs.get("windows_compiler_flags", [])
     kwargs["compiler_flags"] = ["-std=c++17"] + kwargs["compiler_flags"]
     kwargs["compiler_flags"] = ["-Wall"] + kwargs["compiler_flags"]
     kwargs["compiler_flags"] = ["-Werror"] + kwargs["compiler_flags"]
+
+    # RTTI and exceptions allowed for ObjC/iOS, macos, Windows unconditionally for now
+    kwargs["fbobjc_compiler_flags"] = ["-fexceptions"] + kwargs["fbobjc_compiler_flags"]
+    kwargs["windows_compiler_flags"] = ["-fno-exceptions"] + kwargs["windows_compiler_flags"]
+    kwargs["fbobjc_compiler_flags"] = ["-frtti"] + kwargs["fbobjc_compiler_flags"]
+    kwargs["windows_compiler_flags"] = ["-frtti"] + kwargs["windows_compiler_flags"]
+
+    # For now, we allow turning off RTTI and exceptions for android builds only
     if compiler_flags_enable_exceptions:
-        kwargs["compiler_flags"] = ["-fexceptions"] + kwargs["compiler_flags"]
+        kwargs["fbandroid_compiler_flags"] = ["-fexceptions"] + kwargs["fbandroid_compiler_flags"]
     else:
-        kwargs["compiler_flags"] = ["-fno-exceptions"] + kwargs["compiler_flags"]
+        # TODO: fbjni currently DOES NOT WORK with -fno-exceptions, which breaks MOST RN Android modules
+        kwargs["fbandroid_compiler_flags"] = ["-fexceptions"] + kwargs["fbandroid_compiler_flags"]
+        #kwargs["fbandroid_compiler_flags"] = ["-fno-exceptions"] + kwargs["fbandroid_compiler_flags"]
+
     if compiler_flags_enable_rtti:
-        kwargs["compiler_flags"] = ["-frtti"] + kwargs["compiler_flags"]
+        kwargs["fbandroid_compiler_flags"] = ["-frtti"] + kwargs["fbandroid_compiler_flags"]
     else:
-        kwargs["compiler_flags"] = ["-fno-rtti"] + kwargs["compiler_flags"]
+        kwargs["fbandroid_compiler_flags"] = ["-fno-rtti"] + kwargs["fbandroid_compiler_flags"]
 
     native.cxx_library(
         name = name,