Compiler support for C99

From cppreference.net

This section is incomplete
Reason: needs to list C compilers, verification

C99 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray
Universal-character-names in identifiers		3.1	Yes	Yes
Increased translation limits	N590	0.9	N/A
// comments	N644	2.7	Yes	Yes
`restrict` pointers	N448	2.95	Yes	partial *
Enhanced arithmetic types	N815 N601 N620 N638 N657 N694 N809	Yes	partial	Maybe
Flexible array members		3.0	Yes	Yes
Variable-length array (VLA) types	N683	0.9	Yes
Variably-modified (VM) types	N2778	N/A	Yes
Designated initializers	N494	3.0	Yes	Yes
Non-constant initializers		1.21	N/A
Idempotent cvr-qualifiers	N505	3.0	N/A
Trailing comma in enumerator-list		0.9	Yes	Yes
Hexadecimal floating constants	N308	2.8	Yes	Yes
Compound literals	N716	3.1	Yes	Yes
Floating-point environment		partial	partial
Requiring truncation for divisions of signed integer types	N617	0.9	N/A
Implicit return 0 ; in the `main()` function		Yes	Yes	Yes
Declarations and statements in mixed order	N740	3.0	Yes	Yes
init-statement in `for` loops		Yes	Yes	Yes
`inline` functions	N741	4.3	Yes	Yes
Predefined variable `__func__`	N611	2.95	Yes	Yes
Cvr-qualifiers and static in [ ] within function declarations		3.1	Yes
Variadic macros	N707	2.95	Yes	Yes
`_Pragma` preprocessor operator	N634	3.0	Yes	partial *
Standard pragmas for floating-point evaluation	N631 N696	No	No
C99 feature	Paper(s)	GCC	Clang	MSVC	Apple Clang	EDG eccp	Intel C++	Nvidia HPC C++ (ex PGI)*	Nvidia nvcc	Cray

C99
C23