1#############################################################
2## Set up flags based on LOCAL_CXX_STL.
3## Input variables: LOCAL_CXX_STL, my_prefix
4## Output variables: My_cflags, my_c_includes, my_shared_libraries, etc.
5#############################################################
6
7# Select the appropriate C++ STL
8ifeq ($(strip $(LOCAL_CXX_STL)),default)
9    ifndef LOCAL_SDK_VERSION
10        # Platform code. Select the appropriate STL.
11        my_cxx_stl := libc++
12        ifdef LOCAL_IS_HOST_MODULE
13            ifneq (,$(BUILD_HOST_static))
14                my_cxx_stl := libc++_static
15            endif
16        endif
17    else
18        my_cxx_stl := ndk
19    endif
20else
21    my_cxx_stl := $(strip $(LOCAL_CXX_STL))
22    ifdef LOCAL_SDK_VERSION
23        # The NDK has historically used LOCAL_NDK_STL_VARIANT to specify the
24        # STL. An Android.mk that specifies both LOCAL_CXX_STL and
25        # LOCAL_SDK_VERSION will incorrectly try (and most likely fail) to use
26        # the platform STL in an NDK binary. Emit an error to direct the user
27        # toward the correct option.
28        #
29        # Note that we could also accept LOCAL_CXX_STL as an alias for
30        # LOCAL_NDK_STL_VARIANT (and in fact soong does use the same name), but
31        # the two options use different names for the STLs.
32        $(error $(LOCAL_PATH): $(LOCAL_MODULE): Must use LOCAL_NDK_STL_VARIANT rather than LOCAL_CXX_STL for NDK binaries)
33    endif
34endif
35
36my_link_type := dynamic
37ifdef LOCAL_IS_HOST_MODULE
38    ifneq (,$(BUILD_HOST_static))
39        my_link_type := static
40    endif
41    ifeq (-static,$(filter -static,$(my_ldflags)))
42        my_link_type := static
43    endif
44else
45    ifeq (true,$(LOCAL_FORCE_STATIC_EXECUTABLE))
46        my_link_type := static
47    endif
48endif
49
50my_cxx_ldlibs :=
51ifneq ($(filter $(my_cxx_stl),libc++ libc++_static),)
52    ifeq ($($(my_prefix)OS),darwin)
53        # libc++'s headers are annotated with availability macros that indicate
54        # which version of Mac OS was the first to ship with a libc++ feature
55        # available in its *system's* libc++.dylib. We do not use the system's
56        # library, but rather ship our own. As such, these availability
57        # attributes are meaningless for us but cause build breaks when we try
58        # to use code that would not be available in the system's dylib.
59        my_cppflags += -D_LIBCPP_DISABLE_AVAILABILITY
60    endif
61
62    # Note that the structure of this means that LOCAL_CXX_STL := libc++ will
63    # use the static libc++ for static executables.
64    ifeq ($(my_link_type),dynamic)
65        ifeq ($(my_cxx_stl),libc++)
66            my_shared_libraries += libc++
67        else
68            my_static_libraries += libc++_static
69        endif
70    else
71        my_static_libraries += libc++_static
72    endif
73
74    ifdef LOCAL_IS_HOST_MODULE
75        my_cppflags += -nostdinc++
76        my_ldflags += -nostdlib++
77    else
78        my_static_libraries += libc++demangle
79
80        ifeq ($(my_link_type),static)
81            my_static_libraries += libm libc
82            ifeq (arm,$($(my_prefix)$(LOCAL_2ND_ARCH_VAR_PREFIX)ARCH))
83                my_static_libraries += libunwind_llvm
84                my_ldflags += -Wl,--exclude-libs,libunwind_llvm.a
85            else
86                my_static_libraries += libgcc_stripped
87                my_ldflags += -Wl,--exclude-libs,libgcc_stripped.a
88            endif
89        endif
90    endif
91else ifeq ($(my_cxx_stl),ndk)
92    # Using an NDK STL. Handled in binary.mk, except for the unwinder.
93    ifeq (arm,$($(my_prefix)$(LOCAL_2ND_ARCH_VAR_PREFIX)ARCH))
94        my_static_libraries += libunwind_llvm
95        my_ldflags += -Wl,--exclude-libs,libunwind_llvm.a
96    else
97        my_static_libraries += libgcc_stripped
98        my_ldflags += -Wl,--exclude-libs,libgcc_stripped.a
99    endif
100else ifeq ($(my_cxx_stl),libstdc++)
101    $(error $(LOCAL_PATH): $(LOCAL_MODULE): libstdc++ is not supported)
102else ifeq ($(my_cxx_stl),none)
103    ifdef LOCAL_IS_HOST_MODULE
104        my_cppflags += -nostdinc++
105        my_ldflags += -nostdlib++
106    endif
107else
108    $(error $(LOCAL_PATH): $(LOCAL_MODULE): $(my_cxx_stl) is not a supported STL.)
109endif
110