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Error when executing shell command in "Cygwin make"
Here is the case.

path=c:\cygwin\bin; (...omitted... );; (...omitted...)

Take you attention to ';;' - two consecutive semicolon.

In above path environment, executable binaries like 'cp', 'mkdir' that are in 'c:\cywin\bin', works well. But, shell command like 'cmd' raise error something like "command not found".

After removing ';;' - consecutive semicolon (empty path) -, all works well.

So, here is my inference.

"Cywin make" executes command by following order.
  1. searching path environment to file executable binary.
  2. regards command as 'shell command' and try to execute.

In case that ';;' is appeared in the path, "Cygwin make" cannot recognize path after ';;'. So, executables located in the directory those are before ';;' works well. But, those are not, "Cygwin make" treats it as "shell command" and raises error (there is no shell command like this...).

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RVCT and ADS make long jump be possible by adding veneer. But, interestingly, link tool of RVCT and ADS, added veneer only when jump to the code located in other execution area. So, in the case that long jump to the same-execution-area-code is needed, linker generates "memory relocation error" in ADS and RVCT. That's why we need to classify code and put them into several execution area.

TI's TMS470 adds veneer('Trampoline' in TMS) even if target code of long jump is in same execution area. But TMS470 is very slow... :-(

I have no idea about gnu arm eabi tools...

Conflicting symbol name with library is not rare.
So, I want suggest my personal opinion to avoid this.

1. Before release code/library, change all symbol name of source code into unique name (random string) with tool.
2. Determine appropriate symbol name that should be exported.
  (There can be two options. (*a)One is "changing exported symbols into agreed name". (*b)The other is "providing header file that includes all exported symbol with recommended name. And user can re-define necessary or conflicting symbol into expected one")

Let's see the example.

 a. (original source code)
  ...
  MY_UINT32 my_name;
  ...
  MY_UINT16 company_name;
  ..

 b. (symbol-changing-tool setting) - change symbol from 'a.'
  ...
  MY_UINT32 => FooRgYaIIkdjdtq40238dkkRkwUTTT00001
  MY_UINT16 => FooRgYaIIkdjdtq40238dkkRkwUTTT00002
  my_name => FooRgYaIIkdjdtq40238dkkRkwUTTT00003
  compay_name => FooRgYaIIkdjdtq40238dkkRkwUTTT00004
  ...

 c. (auto-modified original source code)
  ...
  FooRgYaIIkdjdtq40238dkkRkwUTTT00001 FooRgYaIIkdjdtq40238dkkRkwUTTT00003;
  ...
  FooRgYaIIkdjdtq40238dkkRkwUTTT00002 FooRgYaIIkdjdtq40238dkkRkwUTTT00004;
  ...

-------- (*a) -------------

 d1. agreed name
  MY_UINT32 => UINT32
  MY_UINT16 => UINT16
  my_name => company_name
  company_name => firm_name

 d2(*a). (symbol-changing-too setting) - change symbol from 'c.' based on 'd.'
  FooRgYaIIkdjdtq40238dkkRkwUTTT00001 => UINT32
  FooRgYaIIkdjdtq40238dkkRkwUTTT00002 => UINT16
  FooRgYaIIkdjdtq40238dkkRkwUTTT00003 => company_name
  FooRgYaIIkdjdtq40238dkkRkwUTTT00004 => firm_name

---------- (*b) ---------

 d. (header file that has recommended symbol)
  /*symbol_match.h */
  /*=============== symbol-matching table ================= */
  ...
  #define UINT32 FooRgYaIIkdjdtq40238dkkRkwUTTT00001
  #define UINT16 FooRgYaIIkdjdtq40238dkkRkwUTTT00002
  #define my_name FooRgYaIIkdjdtq40238dkkRkwUTTT00003
  #define company_name FooRgYaIIkdjdtq40238dkkRkwUTTT00004
  ...

--------------------

 e. (Releasable code - base source code for building library)
  ...
  UINT32 company_name;
  ...
  UINT16 firm_name;
  ...

I think this way is worth considering to make very portable library.