Add support for compiling WebEngine with Clang sanitizer options

This change pipes the already supported Qt sanitize options to
Chromium, so the Chromium build system adds the correct compiler
sanitizer flags.

The change also checks whether the requirements to build a sanitizer
enabled Chromium are met (currently works properly on macOS with an
Apple clang >= 7.3.1, and on Linux with clang + libc++).

Change-Id: Ibab2d5735935ddc92226575fc0e9f5912b807329
Task-number: QTBUG-52656
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

1 files changed, 101 insertions, 0 deletions

diff --git a/tools/qmake/mkspecs/features/functions.prf b/tools/qmake/mkspecs/features/functions.prf
index 047f887d1..6ee9be57d 100644
--- a/tools/qmake/mkspecs/features/functions.prf
+++ b/tools/qmake/mkspecs/features/functions.prf
@@ -76,6 +76,7 @@ defineTest(isPlatformSupported) {
   }
   !isPythonVersionSupported(): return(false)
   !isArchSupported(): return(false)
+  isSanitizerEnabled():!isSanitizerSupported():!forceSanitizerBuild(): return(false)
   return(true)
 }
 
@@ -107,6 +108,106 @@ defineTest(isPythonVersionSupported) {
     return(false)
 }
 
+defineTest(isSanitizerEnabled) {
+  sanitize_address|sanitize_memory|sanitize_undefined|sanitize_thread: return(true)
+  return(false)
+}
+
+defineTest(forceSanitizerBuild) {
+  contains(WEBENGINE_CONFIG, force_sanitizer_build): return(true)
+  skipBuild("Chosen sanitizer configuration is not supported. Use WEBENGINE_CONFIG+=force_sanitizer_build to force build with the chosen sanitizer configuration.")
+  return(false)
+}
+
+defineTest(isSanitizerSupported) {
+  sanitizer_combo_supported = true
+  sanitize_address {
+    asan_supported = false
+    linux-clang-libc++:isSanitizerSupportedOnLinux() {
+      asan_supported = true
+    } else:macos:isSanitizerSupportedOnMacOS() {
+      asan_supported = true
+    }
+    !$$asan_supported {
+      sanitizer_combo_supported = false
+      warning("An address sanitizer-enabled Qt WebEngine build can only be built on Linux or macOS using Clang and libc++.")
+    }
+  }
+
+  sanitize_memory {
+    sanitizer_combo_supported = false
+    warning("A memory sanitizer-enabled Qt WebEngine build is not supported.")
+  }
+
+  sanitize_undefined {
+    ubsan_supported = false
+    linux-clang-libc++:isSanitizerSupportedOnLinux():CONFIG(release, debug|release):!debug_and_release {
+      ubsan_supported = true
+    }
+    !$$ubsan_supported {
+      sanitizer_combo_supported = false
+      warning("An undefined behavior sanitizer-enabled Qt WebEngine build can only be built on Linux using Clang and libc++ in release mode.")
+    }
+  }
+
+  sanitize_thread {
+    tsan_supported = false
+    linux-clang-libc++:isSanitizerSupportedOnLinux() {
+      tsan_supported = true
+    }
+    !$$tsan_supported {
+      sanitizer_combo_supported = false
+      warning("A thread sanitizer-enabled Qt WebEngine build can only be built on Linux using Clang and libc++.")
+    }
+  }
+
+  $$sanitizer_combo_supported: return(true)
+  return(false)
+}
+
+defineTest(isSanitizerSupportedOnLinux) {
+  isSanitizerLinuxClangVersionSupported(): return(true)
+  return(false)
+}
+
+defineTest(isSanitizerSupportedOnMacOS) {
+  isEmpty(QT_APPLE_CLANG_MAJOR_VERSION) {
+    QTWEBENGINE_CLANG_IS_APPLE = false
+  } else {
+    QTWEBENGINE_CLANG_IS_APPLE = true
+  }
+  $$QTWEBENGINE_CLANG_IS_APPLE:isSanitizerMacOSAppleClangVersionSupported(): return(true)
+  else:isSanitizerMacOSClangVersionSupported(): return(true)
+  return(false)
+}
+
+defineTest(isSanitizerMacOSAppleClangVersionSupported) {
+  # Clang sanitizer suppression attributes work from Apple Clang version 7.3.0+.
+  greaterThan(QT_APPLE_CLANG_MAJOR_VERSION, 7): return(true)
+  greaterThan(QT_APPLE_CLANG_MINOR_VERSION, 2): return(true)
+
+  warning("Using Apple Clang version $${QT_APPLE_CLANG_MAJOR_VERSION}.$${QT_APPLE_CLANG_MINOR_VERSION}.$${QT_APPLE_CLANG_PATCH_VERSION}, but at least Apple Clang version 7.3.0 is required to build a sanitizer-enabled Qt WebEngine.")
+  return(false)
+}
+
+defineTest(isSanitizerMacOSClangVersionSupported) {
+  # Clang sanitizer suppression attributes work from non-apple Clang version 3.7+.
+  greaterThan(QT_CLANG_MAJOR_VERSION, 3): return(true)
+  greaterThan(QT_CLANG_MINOR_VERSION, 6): return(true)
+
+  warning("Using Clang version $${QT_CLANG_MAJOR_VERSION}.$${QT_CLANG_MINOR_VERSION}, but at least Clang version 3.7 is required to build a sanitizer-enabled Qt WebEngine.")
+  return(false)
+}
+
+defineTest(isSanitizerLinuxClangVersionSupported) {
+  # Clang sanitizer suppression attributes work from Clang version 3.7+.
+  greaterThan(QT_CLANG_MAJOR_VERSION, 3): return(true)
+  greaterThan(QT_CLANG_MINOR_VERSION, 6): return(true)
+
+  warning("Using Clang version $${QT_CLANG_MAJOR_VERSION}.$${QT_CLANG_MINOR_VERSION}, but at least Clang version 3.7 is required to build a sanitizer-enabled Qt WebEngine.")
+  return(false)
+}
+
 defineTest(isGCCVersionSupported) {
   # The below will work for gcc 4.7 and up and also match gcc 5
   greaterThan(QT_GCC_MINOR_VERSION, 6):return(true)