cmake: default to c99 on android

Author: ethomson

CMakeLists.txt

@@ -53,7 +53,12 @@ option(SONAME                  "Set the (SO)VERSION of the target"
 option(DEPRECATE_HARD          "Do not include deprecated functions in the library"    OFF)
 
 # Compilation options
+# Default to c99 on Android Studio for compatibility; c90 everywhere else
+if("${CMAKE_SYSTEM_NAME}" STREQUAL "Android")
+   set(CMAKE_C_STANDARD        "99" CACHE STRING "The C standard to compile against")
+else()
    set(CMAKE_C_STANDARD        "90" CACHE STRING "The C standard to compile against")
+endif()
 option(CMAKE_C_EXTENSIONS      "Whether compiler extensions are supported"             OFF)
 option(ENABLE_WERROR           "Enable compilation with -Werror"                       OFF)