Add CMAKE_C_FLAGS for clang-3

builder/actions/cmake.py

@@ -2,8 +2,10 @@
 # SPDX-License-Identifier: Apache-2.0.
 
 import os
+import pprint
 import re
 import shutil
+from collections import defaultdict
 from functools import lru_cache, partial
 from pathlib import Path
 
@@ -100,6 +102,28 @@ def _project_dirs(env, project):
     return source_dir, build_dir, install_dir
 
 
+def _merge_cmake_lang_flags(cmake_args):
+    print("=== _merge_cmake_lang_flags: cmake args")
+    pprint.pprint(cmake_args, indent=4, depth=4)
+    pattern = re.compile(r'''-D(CMAKE_C(?:XX)?_FLAGS)=["']?([^"']+)''')
+
+    new_cmake_args = []
+
+    cmake_lang_flags = defaultdict(list)
+    for arg in cmake_args:
+        m = pattern.match(arg)
+        if m:
+            cmake_lang_flags[m.group(1)].append(m.group(2))
+        else:
+            new_cmake_args.append(arg)
+
+    pprint.pprint(cmake_lang_flags, indent=4, depth=4)
+
+    for (k, v) in cmake_lang_flags.items():
+        new_cmake_args.append('-D{}={}'.format(k, ' '.join(v)))
+
+    return new_cmake_args
+
 def _build_project(env, project, cmake_extra, build_tests=False, args_transformer=None, coverage=False):
     sh = env.shell
     config = project.get_config(env.spec)
@@ -135,6 +159,7 @@ def _build_project(env, project, cmake_extra, build_tests=False, args_transforme
 
     # Set compiler flags
     compiler_flags = []
+    c_path = None
     if toolchain.compiler != 'default' and toolchain.compiler != 'msvc' and not toolchain.cross_compile:
         c_path = toolchain.compiler_path()
         cxx_path = toolchain.cxx_compiler_path()
@@ -177,6 +202,13 @@ def _build_project(env, project, cmake_extra, build_tests=False, args_transforme
         else:
             raise Exception('--coverage only support GCC as compiler. Current compiler is: {}'.format(c_path))
 
+    # If there are multiple of the same -DCMAKE_<LANG>_FLAGS arguments, CMake takes only the last one.
+    # Since -DCMAKE_<LANG>_FLAGS can be set in multiple places (e.g. in a default config for a specific platform or
+    # compiler, in a user project's config, in this Python module, etc.), we should merge language flags into one per
+    # language.
+    cmake_args = _merge_cmake_lang_flags(cmake_args)
+    print("=== _build_project: cmake_args: {}".format(cmake_args))
+
     # Allow caller to programmatically tweak the cmake_args,
     # as a last resort in case data merging wasn't working out
     if args_transformer:
@@ -199,7 +231,7 @@ def _build_project(env, project, cmake_extra, build_tests=False, args_transforme
 
     # build & install
     sh.exec(*toolchain.shell_env, cmake, "--build", project_build_dir, "--config",
-            build_config, "--target", "install", working_dir=working_dir, check=True)
+            build_config, "--verbose", "--target", "install", working_dir=working_dir, check=True)
 
 
 class CMakeBuild(Action):

builder/core/data.py

@@ -509,7 +509,8 @@ class PKG_TOOLS(Enum):
                 'c': "clang-3.9",
                 'cxx': "clang++-3.9",
                 # specific version number in use
-                'releases': ['3.9']
+                'releases': ['3.9'],
+                'cmake_args': ['-DCMAKE_C_FLAGS=-Wno-missing-field-initializers'],
             },
             '6': {
                 'c': "clang-6.0",