[bugfix gcc_arm] build+make <-> export project+make: different results

when in target.json "default_build": "small" is configured
- build.py+make.py
  - uses linker option --specs=nano.specs
  - macro MBED_RTOS_SINGLE_THREAD is defined
- exporting with project.py + make Makefile
  - doesn't use the linker option --specs=nano.specs
  - doesn't contain macro MBED_RTOS_SINGLE_THREAD

Author: ohagendorf

tools/toolchains/gcc.py

@@ -285,13 +285,17 @@ def __init__(self, target, options=None, notify=None, macros=None, silent=False,
 
         if use_nano:
             self.ld.append("--specs=nano.specs")
+            self.flags['ld'].append("--specs=nano.specs")
             self.cc += ["-DMBED_RTOS_SINGLE_THREAD"]
             self.cppc += ["-DMBED_RTOS_SINGLE_THREAD"]
+            self.macros.extend(["MBED_RTOS_SINGLE_THREAD"])
 
         if target.name in ["LPC1768", "LPC4088", "LPC4088_DM", "LPC4330", "UBLOX_C027", "LPC2368", "ARM_BEETLE_SOC"]:
             self.ld.extend(["-u _printf_float", "-u _scanf_float"])
+            self.flags['ld'].extend(["-u _printf_float", "-u _scanf_float"])
         elif target.name in ["RZ_A1H", "VK_RZ_A1H", "ARCH_MAX", "DISCO_F407VG", "DISCO_F429ZI", "DISCO_F469NI", "NUCLEO_F401RE", "NUCLEO_F410RB", "NUCLEO_F411RE", "NUCLEO_F429ZI", "NUCLEO_F446RE", "NUCLEO_F446ZE", "ELMO_F411RE", "MTS_MDOT_F411RE", "MTS_DRAGONFLY_F411RE", "DISCO_F746NG"]:
             self.ld.extend(["-u_printf_float", "-u_scanf_float"])
+            self.flags['ld'].extend(["-u_printf_float", "-u_scanf_float"])
 
         self.sys_libs.append("nosys")