Intel C++

Intel C++ Compiler for Linux

User's Guide

Compiler reference

Compiler man

Compiler options

This option enables language compatibility with the gcc option -ansi and provides the same level of ANSI standard conformance as that option.
This option tells the compiler to naturally align variables and arrays. It forces the following natural alignment:
double8 bytes
long long8 bytes
long double16 bytes
If you are not interacting with system libraries or other libraries that are compiled without -align, this option can improve performance by reducing misaligned accesses. caustion:If you are interacting with system libraries or other libraries that are without -align, your application may not perform as expected.
This option tells the compiler to assume that the program adheres to ISO C Standard aliasability rules. If your program adheres to these rules, then this option allows the compiler to optimize more aggressively. If it doesn't adhere to these rules, then it can cause the compiler to generate incorrect code.
Determines whether warning messages are disabled or enabled.
n=0displays errors.
n=1displays warnings and errors.
n=2displays remarks, warnings, and errors. DEFAULT
n=3displays remarks, warnings, and errors.
n=4displays remarks, warnings, and errors.
-Obn (old), -inline-level=n
This option specifies the level of inline function expansion. Inlining procedures can greatly improve the run-time performance of certain programs.
n=0Disables inlining of user-defined functions. Note that statement functions are always inlined.
n=1Enables inlining when an inline keyword or an inline attribute is specified. Also enables inlining according to the C++ language.
n=2Enables inlining of any function at the compiler's discretion.
Enables additional interprocedural optimizations for single file compilation.
Enables the parallelizer to generate multi-threaded code based on the OpenMP directives.


This option improves precision of floating-point divides. It has a slight impact on speed.
-x(a)Z (i32, i64em)
CPUに最適化されたコードを(SSEx等)作成する.(a:alternative?: CPUが分かっているならaを抜いて決め打ち。でも必ずしも「決め打ち」が最適とは限らないfileintel compiler for Linux part2.htm参照)。