From 761f506578ce8e32451d1980ed84d3bd0a05a504 Mon Sep 17 00:00:00 2001
From: "Thiago Marcos P. Santos" <tmpsantos@gmail.com>
Date: Mon, 7 Aug 2017 15:04:08 +0300
Subject: [core] Do not use polymorphic lambda

Crashes with GCC 5.2.0 needed by Qt Automotive.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68278
---
 DEVELOPING.md                     | 11 +++++
 src/mbgl/renderer/render_tile.cpp | 86 +++++++++++++++++++++++----------------
 2 files changed, 63 insertions(+), 34 deletions(-)

diff --git a/DEVELOPING.md b/DEVELOPING.md
index c5c5c53f8a..f70d1f94ea 100644
--- a/DEVELOPING.md
+++ b/DEVELOPING.md
@@ -110,3 +110,14 @@ constexpr bool test2(int i) {
 
 - Either remove `constexpr` specifier or replace it with `inline` in case of
   functions
+
+
+## [Polymorphic lambdas](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68278)
+
+GCC 5.2.0 crashes with polymorphic lambdas and this version of the compiler
+is currently used in Qt Automotive. Luckily polymorphic lambdas are rarely
+used/needed but we had one incident fixed by #9665.
+
+### Workarounds
+
+- Copy & Paste™ the code.
diff --git a/src/mbgl/renderer/render_tile.cpp b/src/mbgl/renderer/render_tile.cpp
index c9912f0563..8df31f8d7c 100644
--- a/src/mbgl/renderer/render_tile.cpp
+++ b/src/mbgl/renderer/render_tile.cpp
@@ -74,57 +74,75 @@ void RenderTile::finishRender(PaintParameters& parameters) {
     static const style::Properties<>::PossiblyEvaluated properties {};
     static const DebugProgram::PaintPropertyBinders paintAttibuteData(properties, 0);
 
-    auto draw = [&] (Color color, const auto& vertexBuffer, const auto& indexBuffer, const auto& segments, auto drawMode) {
+    if (parameters.debugOptions & (MapDebugOptions::Timestamps | MapDebugOptions::ParseStatus)) {
+        if (!tile.debugBucket || tile.debugBucket->renderable != tile.isRenderable() ||
+            tile.debugBucket->complete != tile.isComplete() ||
+            !(tile.debugBucket->modified == tile.modified) ||
+            !(tile.debugBucket->expires == tile.expires) ||
+            tile.debugBucket->debugMode != parameters.debugOptions) {
+            tile.debugBucket = std::make_unique<DebugBucket>(
+                tile.id, tile.isRenderable(), tile.isComplete(), tile.modified,
+                tile.expires, parameters.debugOptions, parameters.context);
+        }
+
         parameters.programs.debug.draw(
             parameters.context,
-            drawMode,
+            gl::Lines { 4.0f * parameters.pixelRatio },
             gl::DepthMode::disabled(),
             parameters.stencilModeForClipping(clip),
             gl::ColorMode::unblended(),
             DebugProgram::UniformValues {
                 uniforms::u_matrix::Value{ matrix },
-                uniforms::u_color::Value{ color }
+                uniforms::u_color::Value{ Color::white() }
             },
-            vertexBuffer,
-            indexBuffer,
-            segments,
+            *tile.debugBucket->vertexBuffer,
+            *tile.debugBucket->indexBuffer,
+            tile.debugBucket->segments,
             paintAttibuteData,
             properties,
             parameters.state.getZoom(),
             "debug"
         );
-    };
-
-    if (parameters.debugOptions & (MapDebugOptions::Timestamps | MapDebugOptions::ParseStatus)) {
-        if (!tile.debugBucket || tile.debugBucket->renderable != tile.isRenderable() ||
-            tile.debugBucket->complete != tile.isComplete() ||
-            !(tile.debugBucket->modified == tile.modified) ||
-            !(tile.debugBucket->expires == tile.expires) ||
-            tile.debugBucket->debugMode != parameters.debugOptions) {
-            tile.debugBucket = std::make_unique<DebugBucket>(
-                tile.id, tile.isRenderable(), tile.isComplete(), tile.modified,
-                tile.expires, parameters.debugOptions, parameters.context);
-        }
 
-        draw(Color::white(),
-             *tile.debugBucket->vertexBuffer,
-             *tile.debugBucket->indexBuffer,
-             tile.debugBucket->segments,
-             gl::Lines { 4.0f * parameters.pixelRatio });
-
-        draw(Color::black(),
-             *tile.debugBucket->vertexBuffer,
-             *tile.debugBucket->indexBuffer,
-             tile.debugBucket->segments,
-             gl::Lines { 2.0f * parameters.pixelRatio });
+        parameters.programs.debug.draw(
+            parameters.context,
+            gl::Lines { 2.0f * parameters.pixelRatio },
+            gl::DepthMode::disabled(),
+            parameters.stencilModeForClipping(clip),
+            gl::ColorMode::unblended(),
+            DebugProgram::UniformValues {
+                uniforms::u_matrix::Value{ matrix },
+                uniforms::u_color::Value{ Color::black() }
+            },
+            *tile.debugBucket->vertexBuffer,
+            *tile.debugBucket->indexBuffer,
+            tile.debugBucket->segments,
+            paintAttibuteData,
+            properties,
+            parameters.state.getZoom(),
+            "debug"
+        );
     }
 
     if (parameters.debugOptions & MapDebugOptions::TileBorders) {
-        draw(Color::red(),
-             parameters.staticData.tileVertexBuffer,
-             parameters.staticData.tileBorderIndexBuffer,
-             parameters.staticData.tileBorderSegments,
-             gl::LineStrip { 4.0f * parameters.pixelRatio });
+        parameters.programs.debug.draw(
+            parameters.context,
+            gl::LineStrip { 4.0f * parameters.pixelRatio },
+            gl::DepthMode::disabled(),
+            parameters.stencilModeForClipping(clip),
+            gl::ColorMode::unblended(),
+            DebugProgram::UniformValues {
+                uniforms::u_matrix::Value{ matrix },
+                uniforms::u_color::Value{ Color::red() }
+            },
+            parameters.staticData.tileVertexBuffer,
+            parameters.staticData.tileBorderIndexBuffer,
+            parameters.staticData.tileBorderSegments,
+            paintAttibuteData,
+            properties,
+            parameters.state.getZoom(),
+            "debug"
+        );
     }
 }
 
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