Add build system support for cross compilation

This patch adds support for inheriting target specific cross-compile
settings from Qt.

Change-Id: I964297d776bcc5ac169ce09a52f661d08c5b4b9d
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>
Reviewed-by: Arvid Nilsson <anilsson@blackberry.com>

5 files changed, 91 insertions, 4 deletions

diff --git a/build/build.pro b/build/build.pro
index 930452e63..9f955a16e 100644
--- a/build/build.pro
+++ b/build/build.pro
@@ -4,9 +4,38 @@
 
 TEMPLATE = aux
 
+GYP_ARGS = "-D qt_cross_compile=0"
+cross_compile {
+    GYP_ARGS = "-D qt_cross_compile=1 -D os_posix=1"
+    TOOLCHAIN_SYSROOT = $$[QT_SYSROOT]
+    !isEmpty(TOOLCHAIN_SYSROOT): GYP_ARGS += "-D sysroot=\"$${TOOLCHAIN_SYSROOT}\""
+
+    contains(QT_ARCH, "arm") {
+        # Extract ARM specific compiler options that we have to pass to gyp
+        MARCH = $$extractCFlag("-march=.*")
+        MFPU = $$extractCFlag("-mfpu=.*")
+        MTUNE = $$extractCFlag("-mtune=.*")
+        MFLOAT = $$extractCFlag("-mfloat-abi=.*")
+        MARMV = $$replace(MARCH, "armv",)
+        MARMV = $$split(MARMV,)
+        MARMV = $$member(MARMV, 0)
+        MTHUMB = 0
+        contains(QMAKE_CFLAGS, "-mthumb"): MTHUMB = 1
+        NEON = 0
+        contains(MFPU, "neon"): NEON = 1
+
+        GYP_ARGS += "-D target_arch=arm -D arm_version=\"$$MARMV\" -D arm_arch=\"$$MARCH\"" \
+                    "-D arm_tune=\"$$MTUNE\" -D arm_fpu=\"$$MFPU\" -D arm_float_abi=\"$$MFLOAT\"" \
+                    "-D arm_thumb=\"$$MTHUMB\" -D arm_neon=\"$$NEON\""
+    }
+
+    # Needed for v8, see chromium/v8/build/toolchain.gypi
+    GYP_ARGS += "-D CXX=\"$$which($$QMAKE_CXX)\""
+}
+
 !build_pass {
-  message(Running Gyp...)
-  !system(python ./gyp_qtwebengine): error("-- running gyp_qtwebengine failed --")
+  message(Running gyp_qtwebengine $${GYP_ARGS}...)
+  !system("python ./gyp_qtwebengine $${GYP_ARGS}"): error("-- running gyp_qtwebengine failed --")
 }
 
 ninja.target = invoke_ninja
diff --git a/build/gyp_qtwebengine b/build/gyp_qtwebengine
index 8a5695ed2..e715cb821 100755
--- a/build/gyp_qtwebengine
+++ b/build/gyp_qtwebengine
@@ -28,6 +28,7 @@ import gyp
 
 # Add paths so that pymod_do_main(...) can import files.
 sys.path.insert(1, os.path.join(chrome_src, 'tools', 'grit'))
+sys.path.insert(1, os.path.join(chrome_src, 'tools', 'generate_shim_headers'))
 
 sys.path.insert(1, os.path.join(chrome_src, 'third_party', 'WebKit',
     'Source', 'core', 'core.gyp', 'scripts'))
@@ -135,6 +136,10 @@ if __name__ == '__main__':
   args.extend(["--depth=" + chrome_src])
   args.extend(['-D', 'qtwebengine_src_dir=' + qtwebengine_src])
   args.extend(['-D', 'chromium_src_dir=' + chrome_src])
+
+  if 'qt_cross_compile=1' in sys.argv:
+    os.environ['GYP_CROSSCOMPILE'] = '1'
+
   # linux_use_gold_binary currently relies on a hardcoded relative path from chromium/src/out/(Release|Debug)
   # Disable it along with the -Wl,--threads flag just in case gold isn't installed on the system.
   args.extend(['-D', 'linux_use_gold_binary=0'])
diff --git a/build/qmake/mkspecs/features/functions.prf b/build/qmake/mkspecs/features/functions.prf
index 78a0272a0..9d90d67bd 100644
--- a/build/qmake/mkspecs/features/functions.prf
+++ b/build/qmake/mkspecs/features/functions.prf
@@ -18,6 +18,12 @@ defineReplace(getConfigDir) {
   return("Debug")
 }
 
+defineReplace(extractCFlag) {
+    OPTION = $$find(QMAKE_CFLAGS, $$1)
+    OPTION = $$split(OPTION, =)
+    return ($$member(OPTION, 1))
+}
+
 defineReplace(findMocables) {
   input = $$1
   for (file, input): \
diff --git a/build/qmake_extras/target/target.pro b/build/qmake_extras/target/target.pro
index 39e0b9e32..6d9f414c3 100644
--- a/build/qmake_extras/target/target.pro
+++ b/build/qmake_extras/target/target.pro
@@ -1,10 +1,29 @@
 # Prevent generating a makefile that attempts to create a lib
 TEMPLATE = aux
 
+TOOLCHAIN_INCLUDES = $${QMAKE_INCDIR_EGL} $${INCLUDEPATH} $${QMAKE_INCDIR}
+
 GYPI_CONTENTS += "    ['CC', '$$which($$QMAKE_CC)']," \
                  "    ['CXX', '$$which($$QMAKE_CXX)']," \
                  "    ['LD', '$$which($$QMAKE_LINK)'],"
-GYPI_CONTENTS += "  ],"
+GYPI_CONTENTS += "  ]," \
+                 "  'target_defaults': {" \
+                 "    'target_conditions': [" \
+                 "      ['_toolset==\"target\"', {" \
+                 "        'include_dirs': ["
+for(includes, TOOLCHAIN_INCLUDES) {
+    GYPI_CONTENTS += "          '$$includes',"
+}
+GYPI_CONTENTS += "        ]," \
+                 "        'cflags': ["
+for(cflag, QT_CFLAGS_DBUS) {
+    GYPI_CONTENTS += "          '$$cflag',"
+}
+GYPI_CONTENTS += "        ]," \
+                 "      }]," \
+                 "    ]," \
+                 "  },"
+
 GYPI_CONTENTS += "}"
 
 GYPI_FILE = $$absolute_path('build/qmake_extras.gypi', $$QTWEBENGINE_ROOT)
diff --git a/build/qtwebengine_extras.gypi b/build/qtwebengine_extras.gypi
index dd3d45ac5..2937ee423 100644
--- a/build/qtwebengine_extras.gypi
+++ b/build/qtwebengine_extras.gypi
@@ -19,5 +19,33 @@
       ['exclude', 'browser/renderer_host/render_widget_host_view_qnx\\.(cc|h)$'],
       ['exclude', 'browser/web_contents/web_contents_view_qnx\\.(cc|h)$'],
     ],
-  }
+  },
+  'conditions': [
+    [ 'OS=="linux" and qt_cross_compile==1', {
+      'target_defaults': {
+        'defines': [
+          'TOOLKIT_QT',
+        ],
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'ldflags!': ['-L/usr/lib'], # garbage added by icu-config
+            'conditions': [
+              [ '_target_name=="gl"', {
+                'defines': [
+                  'GL_GLEXT_PROTOTYPES',
+                  'EGL_EGLEXT_PROTOTYPES',
+                ],
+              }],
+              ['_type=="shared_library"', {
+                'ldflags': [
+                  # Tell the linker to prefer symbols within the library before looking outside
+                  '-Wl,-shared,-Bsymbolic',
+                ],
+              }],
+            ],
+          }],
+        ],
+      },
+    }],
+  ],
 }