3.2. C99 language features available in
C90
The compiler supports numerous extensions to the ISO C90 standard,
for example, C99-style // comments.
These extensions are available if the source language is C90
and you are compiling in non strict mode.
These extensions are not available if the source language
is C90 and the compiler is restricted to compiling strict C90 using
the --strict compiler option.
Note
Language features of Standard C and Standard C++, for example
C++-style // comments, might be similar to the
C90 language extensions described in this section. Such features
continue to remain available if you are compiling strict Standard
C or strict Standard C++ using the --strict compiler
option.
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