Merge pull request #4369 from mysterywolf/removeminilibc

[libc]移除minilibc 并将其职能并入newlibc中

components/libc/compilers/newlib/SConscript

@@ -1,21 +1,30 @@
 from building import *
 Import('rtconfig')
 
-src = Glob('*.c')
+src = []
 cwd = GetCurrentDir()
 group = []
 
 CPPPATH = [cwd]
-CPPDEFINES = ['RT_USING_NEWLIB']
-
-# link with libc and libm:
-# libm is a frequently used lib. Newlib is compiled with -ffunction-sections in
-# recent GCC tool chains. The linker would just link in the functions that have
-# been referenced. So setting this won't result in bigger text size.
-LIBS = ['c', 'm']
 
 if rtconfig.PLATFORM == 'gcc':
-    group = DefineGroup('libc', src, depend = ['RT_USING_LIBC'], 
-        CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES, LIBS = LIBS)
+    if GetDepend('RT_USING_LIBC'):
+        CPPDEFINES = ['RT_USING_NEWLIB']
+        # link with libc and libm:
+        # libm is a frequently used lib. Newlib is compiled with -ffunction-sections in
+        # recent GCC tool chains. The linker would just link in the functions that have
+        # been referenced. So setting this won't result in bigger text size.
+        LIBS = ['c', 'm']
+
+        src += Glob('*.c')
+        SrcRemove(src, ['minilib.c'])
+        if GetDepend('RT_USING_MODULE') == False:
+            SrcRemove(src, ['libc_syms.c'])
+    else:
+        src += ['minilib.c']
+        CPPDEFINES = []
+        LIBS = []
+
+    group = DefineGroup('libc', src, depend = [], CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES, LIBS = LIBS)
 
 Return('group')

components/libc/compilers/newlib/minilib.c

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-02-23     Meco Man     first version
+ */
+
+#include <reent.h>
+#include <rtthread.h>
+
+void * _sbrk_r(struct _reent *ptr, ptrdiff_t incr)
+{
+    /* no use this routine to get memory */
+    return RT_NULL;
+}