`-O ' doesn 't turn on `-ftree-sra ' for the Ada compiler. This option must be explicitly specified on the command line to be enabled for the Ada compiler. `-O2 ' Optimize even more. GCC performs nearly all supported optimizations that do not involve a space-speed tradeoff. The comp...
lot more memory for a large function. With `-O ', the compiler tries to reduce code size and execution time, without performing any optimizations that take a great deal of compilation time. `-O ' turns on the following optimization flags: -fdefer-pop -fdelayed-branch -fguess-branch-proba...
`-O'also turns on `-fomit-frame-pointer'on machines where doing ## ’-O‘也打开-fomit-frame-pointer标志当机器so does not interfere with debugging. 这样做不会影响干涉调试。 `-O'doesn't turn on `-ftree-sra'for the Ada compiler. This option must be explicitly specified on the command l...
The compiler does not perform loop unrolling or function inlining when you specify `-O2 '. As compared to `-O ', this option increases both compilation time and the performance of the generated code.`-O2 ' turns on all optimization flags specified by `-O '. turns on the following ...
c 文件) --cpp Switch to C++ mode (default for .cpp files) 切换到C++模式 (默认.cpp 文件) -O0 Minimum optimization 最小优化级别 -O1 Restricted optimization for debugging 受限的调试级别优化 -O2 High optimization 高优化 -O3 Maximum optimization 最大优化 -Ospace Optimize for codesize 对代码大小...
# 0 = turn off optimization. s = optimize for size. # (Note: 3 is not always the best optimization level. See avr-libc FAQ.) OPT = 00 # Debugging format. # Native formats for AVR-GCC's -g are stabs [default], or dwarf-2. # AVR (extended) COFF requires stabs, plus an avr-...
OPTIMIZATION AND DEBUGGING 没有代码优化的时候,GCC的一个重要目标是尽量缩短编译时间,并保证产生的代码在调试环境下的行为正确。比如,在优化过的代码里,一个变量如果在循环里多次计算,但是值其实没有变化,那么编译器可以把它移到循环的外面,只计算一次。虽然这是可行了(当然,只要不改变程序的运行结果),但是这使你...
196. -fgo-optimize- Turn on optimization passes in the frontend 197. -fgo-pkgpath= Set Go package path 198. -fgo-prefix= Set package-specific prefix for exported Go n ames 199. -fgo-relative-import-path= -fgo-relative-import-path= Treat a rela tive 200. import as relative to path 20...
GCC doesn't understand where the value comes from. So in turn, it doesn't know that the variable 'var1' is actually used unless you tell it explicitly by the used attribute. (An unused variable can be elided from the executable object as a simple optimization.)...
For example, to display all the target-specific optimization options, use: --help=target,optimizers The --help= option can be repeated on the command line. Each successive use displays its requested class of options, skipping those that have already been displayed. If the -Q option appears ...