I have been reviewing old manuals of GCC. The first reference to "noreturn" and "longjmp" together is found in v4.0. I have thus decided to go the daring route and define a new macro, ecl_attr_noreturn as __attribute__((noreturn)) for all versions >= 4.0  The result is a tremendous size reduction in the core, of about 17k! Not bad for starters.

$ size build.attr/libecl.dylib 
__TEXT __DATA __OBJC others dec hex
1318912 253952 0 532480 2105344 202000
$ size build/libecl.dylib 
__TEXT __DATA __OBJC others dec hex
1335296 253952 0 532480 2121728 206000

Instituto de Física Fundamental, CSIC
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