C99 Extensions Supported in C89 Mode in TI Compilers

In C89 mode, the compiler supports selected C99 features as language extensions.

This page applies to compiler releases starting with the following versions. See Production Compiler Releases for information on release availability.

Target	Release	Compiler User’s Guide
ARM	5.2.0	spnu151
ARP32	1.1.0	N/A
C2000	6.3.0	spru514
C6000	7.5.0	spru187
MSP430	4.3.0	slau132
PRU	1.1.0	N/A

For older compilers, see C99 Extensions Supported in C89 Mode in TI Compilers (06Q1-13Q2)

Enabling C99 Language Extensions

Some C99 features are always enabled, but some are only available depending on the language mode.

By default, the compiler is in relaxed C89 mode, and all of the supported C99 extensions are enabled.

In strict ANSI mode, features which would conflict with some strictly compatible program are disabled.

Language Features

This table lists the supported C99 language features and shows when they are enabled. These C99 features are linked to the language conformance mode in use.

Feature	Relaxed	Strict	Comments
Restricted pointers	y	n	restrict keyword, __restrict is equivalent and allowed always
Flexible array member	y	n	Support GCC [0], not C99 []
long long type	y	y	--
Universal character names	y	n	\u and \U
Compound literals	y	n	--
Non-constant initializers	y	n	--
Designated initializers	y	n	--
C++ style // comments	y	n	Warnings rather than errors in strict
inttypes.h	y	y	--
stdint.h	y	y	--
Mixed declarations and code	y	n	--
Variadic macros	y	n	--
Additional math functions in math.h	y	y	cosf, acosh, exp2 et al. for ARM, C6x and C55x only
inline keyword	y	n	__inline is still allowed
snprintf family of functions in stdio.h	y	y	--
stdbool.h	y	y	--
_Pragma preprocessor operator	y	y	--
__func__ predefined identifier	y	n	--
Conversion of array to pointer not limited to Lvalues	y	n	--