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Author: hugueskamba

tools/build_api.py

@@ -48,7 +48,7 @@
 from .libraries import Library
 from .toolchains import TOOLCHAIN_CLASSES, TOOLCHAIN_PATHS
 from .toolchains.arm import UARM_TOOLCHAIN_WARNING
-from .toolchains.mbed_toolchain import is_std_c_lib_supported_instead_small_c_lib
+from .toolchains.mbed_toolchain import replace_small_c_lib
 from .config import Config
 
 RELEASE_VERSIONS = ['2', '5']
@@ -253,9 +253,9 @@ def find_valid_toolchain(target, toolchain):
             ):
                 end_warnings.append(UARM_TOOLCHAIN_WARNING)
 
-            if is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
+            if replace_small_c_lib(target, toolchain, True):
                 warning = (
-                    "Warning: We noticed that you are using target.c_lib set to small.\n"
+                    "Warning: We noticed that target.c_lib is set to small.\n"
                     "As the {} target does not support a small C library for the {} toolchain,\n"
                     "we are using the standard C library instead. "
                 ).format(target.name, toolchain)

tools/toolchains/arm.py

@@ -27,7 +27,7 @@
 from distutils.version import LooseVersion
 
 from tools.toolchains.mbed_toolchain import (
-    mbedToolchain, TOOLCHAIN_PATHS, is_std_c_lib_supported_instead_small_c_lib
+    mbedToolchain, TOOLCHAIN_PATHS, replace_small_c_lib
 )
 from tools.utils import mkdir, NotSupportedException, run_cmd
 from tools.resources import FileRef
@@ -74,9 +74,7 @@ def __init__(self, target, notify=None, macros=None,
 
         toolchain = "arm"
 
-        if is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
-            # Replace small C lib with std if there is no small C lib support
-            target.c_lib = "std"
+        replace_small_c_lib(target, toolchain)
 
         self.check_c_lib_supported(target, toolchain)
 
@@ -572,9 +570,7 @@ def __init__(self, target, *args, **kwargs):
 
         toolchain = "arm"
 
-        if is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
-            # Replace small C lib with std if there is no small C lib support
-            target.c_lib = "std"
+        replace_small_c_lib(target, toolchain)
 
         self.check_c_lib_supported(target, toolchain)
 

tools/toolchains/gcc.py

@@ -23,7 +23,7 @@
 from distutils.version import LooseVersion
 
 from tools.toolchains.mbed_toolchain import (
-    mbedToolchain, TOOLCHAIN_PATHS, is_std_c_lib_supported_instead_small_c_lib
+    mbedToolchain, TOOLCHAIN_PATHS, replace_small_c_lib
 )
 from tools.utils import run_cmd
 
@@ -58,9 +58,7 @@ def __init__(self, target,  notify=None, macros=None, build_profile=None,
         if hasattr(target, "c_lib"):
             toolchain = "gcc_arm"
 
-            if is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
-                # Replace small C lib with std if there is no small C lib support
-                target.c_lib = "std"
+            replace_small_c_lib(target, toolchain)
 
             self.check_c_lib_supported(target, toolchain)
             c_lib = target.c_lib

tools/toolchains/iar.py

@@ -21,7 +21,7 @@
 from distutils.version import LooseVersion
 
 from tools.toolchains.mbed_toolchain import (
-    mbedToolchain, TOOLCHAIN_PATHS, is_std_c_lib_supported_instead_small_c_lib
+    mbedToolchain, TOOLCHAIN_PATHS, replace_small_c_lib
 )
 from tools.utils import run_cmd
 
@@ -58,9 +58,7 @@ def __init__(self, target, notify=None, macros=None, build_profile=None,
 
         toolchain = "iar"
 
-        if is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
-            # Replace small C lib with std if there is no small C lib support
-            target.c_lib = "std"
+        replace_small_c_lib(target, toolchain)
 
         self.check_c_lib_supported(target, "iar")
 

tools/toolchains/mbed_toolchain.py

@@ -1394,19 +1394,33 @@ def report(self):
         to_ret.update(self.config.report)
         return to_ret
 
-def is_std_c_lib_supported_instead_small_c_lib(target, toolchain):
+def replace_small_c_lib(target, toolchain, check_only=False):
     """
-    Check if the standard C lib should be used instead of the small C lib.
-    Return True if the target does not support a small C lib for a given
-    toolchain but supports the standard C library instead.
+    Replace the small C lib for the standard C lib.
+
+    The replacement occurs only if the small C lib is not supported but the
+    standard C lib is.
+    Return True if the replacement occurs otherwise return None.
+    """
+    if (
+        not is_library_supported("small", target, toolchain)
+        and is_library_supported("std", target, toolchain)
+        and target.c_lib == "small"
+    ):
+        if not check_only:
+            target.c_lib = "std"
+        return True
+
+
+def is_library_supported(lib_type, target, toolchain):
+    """
+    Check if a library type is supported by a toolchain for a given target.
+
+    Return True if the library type is supported, False if not supported, and
+    None if the target does not have support the given toolchain.
     """
     if (
-        hasattr(target, "c_lib")
-        and target.c_lib.lower() == "small"
-        and hasattr(target, "supported_c_libs")
+        hasattr(target, "supported_c_libs")
         and toolchain.lower() in target.supported_c_libs
     ):
-        return (
-            "small" not in target.supported_c_libs[toolchain.lower()]
-            and "std" in target.supported_c_libs[toolchain.lower()]
-        )
+        return lib_type in target.supported_c_libs[toolchain.lower()]