By default IAR generates "transfer of control bypasses initialization"
warnings for C code - it's a legal construct that frequently occurs when
doing Linux-style "goto error". Many occurrences in Nanostack.
Suppress the warning for C only, to align with GCC and ARMCC. Have to
take care not to put it in the "common" section, as this would suppress
it for C++, where it actually is illegal.
### Description
Full paths in the map file are required to have correct memap parsing.
This PR adds the option `--show_full_path` to ARMC6 in every profile.
This option only affects the map file output, so it's safe to add.
This allows minimal debugging and allows tools like
mbed-os-linker-report to work properly.
Because debugging info is kept in .elf file and not flashed to device
there is no side effects to flash sizes.
While ARMC6 does use the same linker (armlink) as ARM Compiler 5, it
is not compatible.
The reason for this incompatibility are twofold:
* armlink may invoke the C preprocessor by adding a shebang
(`#!`) to the top of their input files.
* ARMC6 and ARMC5 differ in how you invoke the preprocessor:
* ARMC5: `#! armcc -E`
* ARMC6: `#! armclang -E`
This forces the tools to rewrite the shebang if it's wrong.
This does not yet handle dependencies properly
Jimmy Brisson
Cruz Monrreal
Kevin Bracey
Bartek Szatkowski
Seppo Takalo
Niklas Hauser
Tony Wu