GCC: Use 'common' flags at link time

According to GCC man:
To use the link-time optimizer, -flto and optimization options should be
specified at compile time and during the final link. It is recommended
that you compile all the files participating in the same link with the
same options and also specify those options at link time.

Author: Filip Jagodzinski

tools/profiles/debug.json

@@ -1,15 +1,15 @@
 {
     "GCC_ARM": {
-        "common": ["-c", "-Wall", "-Wextra",
+        "common": ["-Wall", "-Wextra",
                    "-Wno-unused-parameter", "-Wno-missing-field-initializers",
                    "-fmessage-length=0", "-fno-exceptions",
                    "-ffunction-sections", "-fdata-sections", "-funsigned-char",
                    "-MMD", "-fno-delete-null-pointer-checks",
                    "-fomit-frame-pointer", "-Og", "-g3", "-DMBED_DEBUG",
                    "-DMBED_TRAP_ERRORS_ENABLED=1"],
-        "asm": ["-x", "assembler-with-cpp"],
-        "c": ["-std=gnu11"],
-        "cxx": ["-std=gnu++14", "-fno-rtti", "-Wvla"],
+        "asm": ["-c", "-x", "assembler-with-cpp"],
+        "c": ["-c", "-std=gnu11"],
+        "cxx": ["-c", "-std=gnu++14", "-fno-rtti", "-Wvla"],
         "ld": ["-Wl,--gc-sections", "-Wl,--wrap,main", "-Wl,--wrap,_malloc_r",
                "-Wl,--wrap,_free_r", "-Wl,--wrap,_realloc_r", "-Wl,--wrap,_memalign_r",
                "-Wl,--wrap,_calloc_r", "-Wl,--wrap,exit", "-Wl,--wrap,atexit",

tools/profiles/develop.json

@@ -1,14 +1,14 @@
 {
     "GCC_ARM": {
-        "common": ["-c", "-Wall", "-Wextra",
+        "common": ["-Wall", "-Wextra",
                    "-Wno-unused-parameter", "-Wno-missing-field-initializers",
                    "-fmessage-length=0", "-fno-exceptions",
                    "-ffunction-sections", "-fdata-sections", "-funsigned-char",
                    "-MMD", "-fno-delete-null-pointer-checks",
                    "-fomit-frame-pointer", "-Os", "-g", "-DMBED_TRAP_ERRORS_ENABLED=1"],
-        "asm": ["-x", "assembler-with-cpp"],
-        "c": ["-std=gnu11"],
-        "cxx": ["-std=gnu++14", "-fno-rtti", "-Wvla"],
+        "asm": ["-c", "-x", "assembler-with-cpp"],
+        "c": ["-c", "-std=gnu11"],
+        "cxx": ["-c", "-std=gnu++14", "-fno-rtti", "-Wvla"],
         "ld": ["-Wl,--gc-sections", "-Wl,--wrap,main", "-Wl,--wrap,_malloc_r",
                "-Wl,--wrap,_free_r", "-Wl,--wrap,_realloc_r", "-Wl,--wrap,_memalign_r",
                "-Wl,--wrap,_calloc_r", "-Wl,--wrap,exit", "-Wl,--wrap,atexit",

tools/profiles/release.json

@@ -1,18 +1,18 @@
 {
     "GCC_ARM": {
-        "common": ["-c", "-Wall", "-Wextra",
+        "common": ["-Wall", "-Wextra",
                    "-Wno-unused-parameter", "-Wno-missing-field-initializers",
                    "-fmessage-length=0", "-fno-exceptions",
                    "-ffunction-sections", "-fdata-sections", "-funsigned-char",
                    "-MMD", "-fno-delete-null-pointer-checks",
                    "-fomit-frame-pointer", "-Os", "-flto", "-DNDEBUG", "-g"],
-        "asm": ["-x", "assembler-with-cpp"],
-        "c": ["-std=gnu11"],
-        "cxx": ["-std=gnu++14", "-fno-rtti", "-Wvla"],
+        "asm": ["-c", "-x", "assembler-with-cpp"],
+        "c": ["-c", "-std=gnu11"],
+        "cxx": ["-c", "-std=gnu++14", "-fno-rtti", "-Wvla"],
         "ld": ["-Wl,--gc-sections", "-Wl,--wrap,main", "-Wl,--wrap,_malloc_r",
                "-Wl,--wrap,_free_r", "-Wl,--wrap,_realloc_r", "-Wl,--wrap,_memalign_r",
                "-Wl,--wrap,_calloc_r", "-Wl,--wrap,exit", "-Wl,--wrap,atexit",
-               "-Wl,-n", "-Os", "-flto"]
+               "-Wl,-n"]
     },
     "ARMC6": {
         "common": ["-c", "--target=arm-arm-none-eabi", "-mthumb", "-Oz",

tools/toolchains/gcc.py

@@ -125,7 +125,8 @@ def __init__(self, target,  notify=None, macros=None, build_profile=None,
         self.cppc += self.flags['cxx'] + self.flags['common']
 
         self.flags['ld'] += self.cpu
-        self.ld = [join(tool_path, "arm-none-eabi-gcc")] + self.flags['ld']
+        self.ld = [join(tool_path, "arm-none-eabi-gcc")]
+        self.ld += self.flags['ld'] + self.flags['common']
         self.sys_libs = ["stdc++", "supc++", "m", "c", "gcc", "nosys"]
         self.preproc = [join(tool_path, "arm-none-eabi-cpp"), "-E", "-P"]