9(2x-3)^2=4(2-x)^2_百度知道
9(2x-3)^2=4(2-x)^2
提问者采纳
9(2x-3)^2=4(2-x)^29(2x-3)^2-4(2-x)^2=0(4X-5)(8X-13)=0X=5/4，X=13/8
其他类似问题
其他5条回答
9(2x-3)^2=4(2-x)^2[3(2x-3)]^2-[2(x-2)]^2=0(6x-9)^2-(2x-4)^2=0(6x-9+2x-4)(6x-9-2x+4)=0(8x-13)(4x-5)=0x=13/8,x=5/4
解：9(2x-3)^2=4(2-x)^2 (6x-9)²-(4-2x)²=0(6x-9+4-2x)(6x-9-4+2x)=0(4x-5)(8x-13)=0x1=5/4,x2=13/8
（9（2x-3）^2）-(4（2-x）^2)=0(3(2x-3)+2(2-x))(3(2x-3)-2(2-x))=0(6x-9+4-2x)(6x-9-4+2x)=0(4x-5)(8x-13)=0x=5/4x=13/8
(3*(2x-3)^2=(2*(2-x)^23*(2x-3)=2*(2-x) or 3*(2x-3)= - 2*(2-x)6x-9=4-2x or 6x-9=-4+2x8x=13
or 4x = 5x=13/8 or x=5/4
9(2x-3)^2=4(2-x)^2 9(2x-3)^2-4(2-x)^2=0[3 (2x-3)+2(2-x)][3 (2x-3)-2(2-x)]=0(6x-9+4-2x)(6x-9-4+2x)=0(4x-5)(8x-13)=0x1=5/4x2=13/8
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＞＞＞2.4×9.9+0.24=2.4×（9.9+0.1）[]-六年级数学-魔方格
2.4×9.9+0.24=2.4×（9.9+0.1）
题型：判断题难度：偏易来源：同步题
马上分享给同学
据魔方格专家权威分析，试题“2.4×9.9+0.24=2.4×（9.9+0.1）[]-六年级数学-魔方格”主要考查你对&&运算定律和简便算法&&等考点的理解。关于这些考点的“档案”如下：
现在没空？点击收藏，以后再看。
因为篇幅有限，只列出部分考点，详细请访问。
运算定律和简便算法
学习目标：1、掌握运算定律，并能运用运算定律和性质进行正确、合理、灵活的计算。2、养成良好审题习惯，提高计算能力。运算定律：
加法交换律
两个数相加，交换加数的位置，和不变。
25+14=14+25
加法结合律
三个数相加，先把前两数相加，再同第三个数相加，或者先把后两数相加，再同第一个数相加，它们的和不变。
a+b+c=a+（b+c）
20+14+36= 20+（14+36）
乘法交换律
两个数相乘，交换因数的位置，它们的积不变。
10×12=12×10
乘法结合律
三个数相乘，先把前两个数相乘，再同第三个数相乘，或者先把后两个数相乘，再同第一个数相乘，它们的积不变。
a×b×c= a×（b×c）
12×25×4= 12×（25×4）
乘法分配律
两个数的和同一个数相乘，可以把两个加数分别和这个数相乘，再把两个积相加，结果不变。
（a+b）×c= a×c+b×c
（12+15）×4= 12×4+15×4运算性质：
减法的性质
一个数连续减去几个数等于一个数减去这几个数的和
a-b-b= a-（b+c）
250-18-52= 250-（18+52）
除法的性质
一个数连续除以几个数（0除外）等于一个数除以这几个数的积
a÷b÷c= a÷（b×c）
180÷4÷25= 180÷（4×25）
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3秒自动关闭窗口GCC 4.9.0 发布，提升 C++11 和 C++14 特性
GCC 4.9.0 发布，此版本是个主要版本更新，包括了 GCC 4.8.x 系列和之前的 GCC 版本都没有的新特性，新特性非常之多。下载地址：警告移除 mudflap 运行时检查器，mudflap 选项保留，但没有任何效果.对一些很多老的系统和一些不维护的平台的支持在 4.9 版本中声明为过世的，下一个版本将永久删除，例如 Solaris 9更多移植到& GCC 4.9 的信息请参考 一般优化器改进AddressSanitizer, a fast memory error detector, is now available on ARM.UndefinedBehaviorSanitizer (ubsan), a fast undefined behavior detector,
& & & &has been added and can be enabled via -fsanitize=undefined.
Various computations will be instrumented to detect undefined behavior
at runtime. &UndefinedBehaviorSanitizer is currently available for the C
and C++ languages.Link-time optimization (LTO) improvements:Memory usage building Firefox with debug enabled was reduced from 15GB to
& &3.5GB; link time from 1700 seconds to 350 seconds.Type merging was rewritten. The new implementation is significantly faster
& & &and uses less memory.Better partitioning algorithm resulting in less streaming during
&link time.Early removal of virtual methods reduces the size of object files and
&improves link-time memory usage and compile time.Function bodies are now loaded on-demand and released early improving
&overall memory usage at link time.C++ hidden keyed methods can now be optimized out.When using a linker plugin, compiling with the -flto
& & & & &option now generates slim objects files (.o) which only
& & & & &contain intermediate language representation for LTO. Use & & & & &-ffat-lto-objects to create files which contain
& & & & &additionally the object code. &To generate static libraries suitable
& & & & &for LTO processing, use gcc-ar and & & & & gcc-ranlib; to list symbols from a slim object file use & & & & gcc-nm. (Requires that ar, & & & & ranlib and nm have been compiled with
& & & & plugin support.)Inter-procedural optimization improvements:New type inheritance analysis module improving devirtualization.
&Devirtualization now takes into account anonymous name-spaces and the
&C++11 final keyword.New speculative devirtualization pass (controlled by
&-fdevirtualize-speculatively.Calls that were speculatively made direct are turned back to indirect
&where direct call is not cheaper.Local aliases are introduced for symbols that are known to be
&semantically equivalent across shared libraries improving dynamic
&linking times.Feedback directed optimization improvements:Profiling of programs using C++ inline functions is now more reliable.New time profiling determines typical order in which functions are
&executed.A new function reordering pass (controlled by
&-freorder-functions) significantly reduces
&startup time of large applications. &Until binutils support is
&completed, it is effective only with link-time optimization.Feedback driven indirect call removal and devirtualization now handle
&cross-module calls when link-time optimization is enabled.新语言和语音特性改进Version 4.0 of the
is now supported for the C and C++ compilers.
The new -fopenmp-simd option can be used to enable OpenMP's
SIMD directives, while ignoring other OpenMP directives. The new
option permits to tune the
vectorization cost model for loops annotated with OpenMP and Cilk
Plus simd -Wopenmp-simd warns when
the current costmodel overrides simd directives set by the user.The -Wdate-time option has been added for the C, C++ and
Fortran compilers, which warns when the __DATE__, __TIME__ or __TIMESTAMP__ macros are used.
Those macros might prevent bit-wise-identical reproducible
compilations.AdaGNAT switched to Ada 2012 instead of Ada 2005 by default.C familySupport for colorizing diagnostics emitted by GCC has been added.
will enable it when
& &outputting to terminals, -fdiagnostics-color=always
& &unconditionally. &The GCC_COLORS environment variable
& &can be used to customize the colors or disable coloring.
& &If GCC_COLORS variable is present in the environment,
& &the default is -fdiagnostics-color=auto, otherwise & &-fdiagnostics-color=never.
& &Sample diagnostics output:&&&&$&g++&-fdiagnostics-color=always&-S&-Wall&test.C&&&&test.C:&In&function&‘int&foo()’:&&&&test.C:1:14:&warning:&no&return&statement&in&function&returning&non-void&[-Wreturn-type]
&&&&&int&foo&()&{&}&&&&&&&&&&&&&&&&&&^
&&&&test.C:2:46:&error:&template&instantiation&depth&exceeds&maximum&of&900&(use&-ftemplate-depth=&to&increase&the&maximum)&instantiating&‘struct&X&100&’
&&&&&template&&int&N&&struct&X&{&static&const&int&value&=&X&N-1&::&};&template&struct&X&1000&;&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&^
&&&&test.C:2:46:&&&recursively&required&from&‘const&int&X&999&::value’&&&&test.C:2:46:&&&required&from&‘const&int&X&1000&::value’&&&&test.C:2:88:&&&required&from&here&&&&test.C:2:46:&error:&incomplete&type&‘X&100&’&used&in&nested&name&specifierWith the new , the user can assert that there are no
& &loop-carried dependencies which would prevent concurrent execution of
& &consecutive iterations using SIMD (single instruction multiple data)
& &instructions.Support for
& &added and can be enabled with the -fcilkplus option. &Cilk Plus
& &is an extension to the C and C++ languages to support data and task
& &parallelism. &The present implementation follows ABI version 1.2; all
& &features but _Cilk_for have been implemented.CISO C11 atomics (the _Atomic type specifier and
&qualifier and the &stdatomic.h& header) are now
&supported.ISO C11 generic selections (_Generic keyword) are
&now supported.ISO C11 thread-local storage (_Thread_local,
&similar to GNU C __thread) is now supported.ISO C11 support is now at a similar level of completeness to ISO
&C99 support: substantially complete modulo bugs, extended
&identifiers (supported except for corner cases
&when -fextended-identifiers is used), floating-point
&issues (mainly but not entirely relating to optional C99 features
&from Annexes F and G) and the optional Annexes K (Bounds-checking
&interfaces) and L (Analyzability).A new C extension __auto_type provides a subset of
&the functionality of C++11 auto in GNU C.C++The G++ implementation of
return type deduction for normal
& &functions has been updated to conform to & &,
& &the proposal accepted into the working paper. &Most notably, it adds decltype(auto) for
& &getting decltype semantics rather than the template argument deduction semantics of plain auto:int&&f();
&&&&&&&&&auto&&i1&=&f();&//&int
decltype(auto)&i2&=&f();&//&int&G++ supports
lambda capture initializers:[x&=&42]{&...&};Actually, they have been accepted since GCC 4.5, but now the compiler doesn't
warn about them with -std=c++1y, and supports parenthesized and
brace-enclosed initializers as well.G++ supports
variable length
& &arrays. &G++ has supported GNU/C99-style VLAs for a long time, but now
& &additionally supports initializers and lambda capture by reference. &In
& &C++1y mode G++ will complain about VLA uses that are not permitted by
& &the draft standard, such as forming a pointer to VLA type or
& &applying sizeof to a VLA variable. &Note that it now appears
& &that VLAs will not be part of C++14, but will be part of a separate
& &document and then perhaps C++17.void&f(int&n)&{
&&int&a[n]&=&{&1,&2,&3&};&//&throws&std::bad_array_length&if&n&&&3
&&[&a]{&for&(int&i&:&a)&{&cout&&&&i&&&&&}&}();
&&&a;&//&error,&taking&address&of&VLA
}G++ supports the
[[deprecated]]
& &attribute modulo bugs in the underlying [[gnu::deprecated]] attribute. &Classes
& &and functions can be marked deprecated and a diagnostic message added:class&A;
int&bar(int&n);
#if&__cplusplus&&&201103
class&[[deprecated(&A&is&deprecated&in&C++14;&Use&B&instead&)]]&A;
[[deprecated(&bar&is&&use&foo()&instead&)]]
int&bar(int&n);
int&foo(int&n);
A&&//&warning:&'A'&is&deprecated&:&A&is&deprecated&in&C++14;&Use&B&instead
int&j&=&bar(2);&//&warning:&'int&bar(int)'&is&deprecated&:&bar&is&&use&foo()&insteadG++ supports
digit separators.
& &Long numeric literals can be subdivided with a single quote ' to enhance readability:int&i&=&1048576;
int&j&=&1'048'576;
int&k&=&0x10'0000;
int&m&=&0'004'000'000;
int&n&=&0b0'0'0;
double&x&=&1.602'176'565e-19;
double&y&=&1.602'176'565e-1'9;G++ supports
polymorphic lambdas.//&a&functional&object&that&will&increment&any&type
auto&incr&=&[](auto&x)&{&return&x++;&};Runtime Library (libstdc++), including:support for &regex&;The associative containers in &map& and & & & & & & &&set& and the unordered associative containers
& & & & & & &in &unordered_map& and &unordered_set&
& & & & & & &meet the allocator-aware co,
& & & including:fixing constexpr member functions without const;implementation of the std::exchange()addreimplemention of std::make_unique;implemention of std::shared_lock;making std::result_of SFINAE-adding operator() to integral_constant;adding user-defined literals for standard library types & & & & & & std::basic_string, std::chrono::duration,
& & & & & & and std::complex;adding two range overloads to non-modifying sequence oprations & & & & & & std::equal and std::mismatch;adding IO manipulatoradding constexpr members to &utility&, & & & & & & &complex&, &chrono&,adding compile-time std::integer_sequence;adding cleaner tmaking &functional&s operator functors easier to use
& & & & & &An implementation of std::experimental::optional.An implementation of std::experimental::string_view.The non-standard function std::copy_exception has been deprecated
& & & &and will be removed in a future version. std::make_exception_ptr
& & & &should be used instead.FortranCompatibility notice:Note that the
has changed for scalar dummy
&arguments of type INTEGER, REAL,
&COMPLEX and LOGICAL, which have
&both the VALUE and the OPTIONAL
&attribute.Due to the support of finalization, the virtual table associated
& & & & &with polymorphic variables has changed. Therefore, code containing & & & & &CLASS should be recompiled, including all files which
& & & & &define derived types involved in the type definition used by
& & & & &polymorphic variables. (Note: Due to the incremented module version,
& & & & &trying to mix old code with new code will usually give an error
& & & & &message.)Module files: The version of the module files (.mod)
& & & & additionally, module files are now compressed.
& & & &Fortran MODULEs compiled by earlier GCC versions have
& & & &to be recompiled, when they are USEd by files compiled
& & & &with GCC 4.9, because GCC 4.9 is not able to read .mod
& & & &files of earlier GCC attempting to do so gives an error
& & & &message. Note: The ABI of the produced assembler data itself has not
& & & &changed: object files and libraries are fully compatible to older
& & & &versions. (Except for the next items.)ABI changes:GNU Fortran no longer deallocates allocatable variables or
& & & &allocatable components of variables declared in the main program. Since
& & & &Fortran 2008, the standard explicitly states that variables declared
& & & &in the Fortran main program automatically have the SAVE
& & & &attribute.When opening files, the close-on-exec flag is set if the system
& & & &supports such a feature. This is generally considered good practice
& & & &these days, but if there is a need to pass file descriptors to child
& & & &processes the parent process must now remember to clear the
& & & &close-on-exec flag by calling fcntl(), e.g. via & & & &ISO_C_BINDING, before executing the child process.The deprecated command-line option -fno-whole-file
& & &has been removed. (-fwhole-file is the default since
& & &GCC 4.6.) -fwhole-file/-fno-whole-file
& & &continue to be accepted but do not influence the code generation.The compiler no longer unconditionally warns
& & &about DO loops with zero iterations. &This warning is now
& & &controlled by the -Wzerotrips option, which is implied by & & &-Wall.The new NO_ARG_CHECK attribute of the
can be used to disable the
& & &type-kind-rank (TKR) argument check for a dummy argument. The feature
& & &is similar to ISO/IEC TS 's TYPE(*), except that
& & &it additionally also disables the rank check. Variables with & & &NO_ARG_CHECK have to be dummy arguments and may only be
& & &used as argument to ISO_C_BINDING's C_LOC
& & &and as actual argument to another NO_ARG_CHECK dummy
& & & also the other constraints of TYPE(*) apply.
& & &The dummy arguments should be declared as scalar or assumed-size
& & &variable of type type(*) (recommended) – or of
& & &type integer, real, complex
& & &or logical. With NO_ARG_CHECK, a pointer
& & &to the data without further type or shape information is passed,
& & &similar to C's void*. Note that also TS 29113's & & &type(*),dimension(..) accepts arguments of any type and
& & & contrary to NO_ARG_CHECK assumed-rank arguments
& & &pass an array descriptor which contains the array shape and stride
& & &of the argument.:Finalization is now supported. Note that finalization is currently
& & & &only done for a subset of the situations in which it should occur.Experimental support for scalar character components with
& & & &deferred length (i.e. allocatable string length) in derived types has
& & & &been added. (Deferred-length character variables are supported since
& & & &GCC 4.6.):When STOP or ERROR STOP is used to terminate
& & & &the execution and any exception (but inexact) is signaling, a warning is
& & & &printed to ERROR_UNIT, indicating which exceptions are
& & & &signaling. The
command-line option can be used to fine-tune
& & & &for which exception the warning should be shown.Rounding on input (READ) is now handled on systems where & & & &strtod honours the rounding mode. (For output, rounding is
& & & &supported since GCC 4.5.) Note that for input, the & & & &compatible rounding mode is handled as nearest
& & & &(i.e., for a tie, rounding to an even last significant
& & & &[cf. IEC ] – while compatible rounds away
& & & &from zero for a tie).GoGCC 4.9 provides a complete implementation of the Go 1.2.1
& & &release.新平台支持AArch64The ARMv8-A crypto and CRC instructions are now supported through
& & & intrinsics. These are enabled when the architecture supports these
& & & and are available through the -march=armv8-a+crc
& & & and -march=armv8-a+crypto options.Initial support for ILP32 has now been added to the
& & & compiler. This is now available through the command line option & & & -mabi=ilp32. Support for ILP32 is
& & & considered experimental as the ABI specification is still beta.Coverage of more of the ISA including the SIMD extensions has
& & & been added. The Advanced SIMD intrinsics have also been improved.The new local register allocator (LRA) is now on by default
& & & for the AArch64 backend.The REE (Redundant extension elimination) pass has now been enabled
& & & by default for the AArch64 backend.Tuning for the Cortex-A53 and Cortex-A57 has been improved.Initial big.LITTLE tuning support for the combination of Cortex-A57
& & & and Cortex-A53 was added through the -mcpu=cortex-a57.cortex-a53 & & &
option.A number of structural changes have been made to both the ARM
& & & and AArch64 backends to facilitate improved code-generation.ARMUse of Advanced SIMD (Neon) for 64-bit scalar computations has been
disabled by default. This was found to generate better code in only
a small number of cases. It can be turned back on with the -mneon-for-64bits option.Further support for the ARMv8-A architecture, notably implementing
& & & the restriction around IT blocks in the Thumb32 instruction set has
& & & been added. The -mrestrict-it option can be used with & & & -march=armv7-a or the -march=armv7ve options
& & & to make code generation fully compatible with the deprecated instructions
& & & in ARMv8-A.Support has now been added for the ARMv7ve variant of the
& & & architecture. This can be used by the -march=armv7ve option.The ARMv8-A crypto and CRC instructions are now supported through
& & & intrinsics and are available through the -march=armv8-a+crc
& & & and mfpu=crypto-neon-fp-armv8 options.LRA is now on by default for the ARM target. This can be turned off
& & & using the -mno-lra option. This option is purely
& & & transitionary command line option and will be removed in a future
& & & release. We are interested in any bug reports regarding functional and
& & & performance regressions with LRA.A new option -mslow-flash-data to improve performance
& & & of programs fetching data on slow flash memory has now been
& & & introduced for the ARMv7-M profile cores.A new option -mpic-data-is-text-relative for targets
& & & that allows data segments to be relative to text segments has
& & & been added. This is on by default for all targets except VxWorks RTP.A number of infrastructural changes have been made to both the ARM
& & & and AArch64 backends to facilitate improved code-generation.GCC now supports Cortex-A12 and the Cortex-R7 through the & & & -mcpu=cortex-a12 and -mcpu=cortex-r7 options.GCC now has tuning for the Cortex-A57 and Cortex-A53
& & & through the -mcpu=cortex-a57 and -mcpu=cortex-a53 & & &
options.Initial big.LITTLE tuning support for the combination of Cortex-A57
& & & and Cortex-A53 was added through the -mcpu=cortex-a57.cortex-a53 & & &
option. Similar support was added for the combination of
& & & Cortex-A15 and Cortex-A7 through the -mcpu=cortex-a15.cortex-a7 & & &
option.Further performance optimizations for the Cortex-A15 and the
& & & Cortex-M4 have been added.A number of code generation improvements for Thumb2 to reduce code
& & & size when compiling for the M-profile processors.IA-32/x86-64-mfpmath=sse is now implied by -ffast-math
on all targets where SSE2 is supported.Intel AVX-512 support was added to GCC. &That includes inline
& & &assembly support, new registers and extending existing ones,
& & &new intrinsics (covered by corresponding testsuite), and basic
& & &autovectorization. &AVX-512 instructions are available via
& & &the following GCC switches: AVX-512 foundation instructions: & & &-mavx512f, AVX-512 prefetch instructions: -mavx512pf,
& & &AVX-512 exponential and reciprocal instructions: -mavx512er,
& & &AVX-512 conflict detection instructions: -mavx512cd.It is now possible to call x86 intrinsics from select functions in
& & &a file that are tagged with the corresponding target attribute without
& & &having to compile the entire file with the -mxxx option.
& & &This improves the usability of x86 intrinsics and is particularly useful
& & &when doing .GCC now supports the new Intel microarchitecture named Silvermont
& & &through -march=silvermont.GCC now supports the new Intel microarchitecture named Broadwell
& & &through -march=broadwell.Optimizing for other Intel microarchitectures have been renamed
& & &to -march=nehalem, westmere, & & &sandybridge, ivybridge, & & &haswell, bonnell.-march=generic has been retuned for better support of
& & &Intel core and AMD Bulldozer architectures. &Performance of AMD K7, K8,
& & &Intel Pentium-M, and Pentium4 based CPUs is no longer considered important
& & &for generic.-mtune=intel can now be used to generate code running
& & &well on the most current Intel processors, which are Haswell
& & &and Silvermont for GCC 4.9.Support to encode 32-bit assembly instructions in 16-bit format
& & &is now available through the -m16 command-line option.Better inlining of memcpy and memset
that is aware of value ranges and produces shorter alignment prologues.-mno-accumulate-outgoing-args is now honored when unwind
& & &information is output. &Argument accumulation is also now turned off
& & &for portions of programs optimized for size.Support for new AMD family 15h processors (Excavator core)
& & & &is now available through the -march=bdver4 and & & & &-mtune=bdver4 options.MSP430A new command-line option -mcpu= has been added to the MSP430 backend.
& &This option is used to specify the ISA to be used. &Accepted values are & &msp430 (the default), msp430x and msp430xv2. &The ISA is no longer deduced
& &from the -mmcu= option as there are far too many different MCU names. &The & &-mmcu= option is still supported, and this is still used to select linker
& &scripts and generate a C preprocessor symbol that will be recognised by the & &msp430.h header file.NDS32A new nds32 port supports the 32-bit architecture from Andes
& & &Technology Corporation.The port provides initial support for the V2, V3, V3m
& & &instruction set architectures.Nios IIA port for the Altera Nios II has been contributed by
& & &Mentor Graphics.PowerPC / PowerPC64 / RS6000GCC now supports Power ISA 2.07, which includes support for Hardware
& &Transactional Memory (HTM), Quadword atomics and several VMX and VSX
& &additions, including Crypto, 64-bit integer, 128-bit integer and
& &decimal integer operations.Support for the POWER8 processor is now available through the & &-mcpu=power8 and -mtune=power8 options.The libitm library has been modified to add a HTM fastpath that
& &automatically uses POWER's HTM hardware instructions when it is
& &executing on a HTM enabled processor.Support for the new powerpc64le-linux platform has been added.
& &It defaults to generating code that conforms to the ELFV2 ABI.S/390, System zSupport for the Transactional Execution Facility included with
& & &the IBM zEnterprise zEC12 processor has been added. &A set of
& & &GCC style builtins as well as XLC style builtins are provided.
& & &The builtins are enabled by default when using
& & &the -march=zEC12 option but can explicitly be
& & &disabled with -mno-htm.
& & &Using the GCC builtins also libitm supports hardware
& & &transactions on S/390.The hotpatch features allows to prepare functions for
& & &hotpatching. &A certain amount of bytes is reserved before the
& & &function entry label plus a NOP is inserted at its very
& & &beginning to implement a backward jump when applying a patch.
& & &The feature can either be enabled via command line
& & &option -mhotpatch for a compilation unit or can be
& & &enabled per function using the hotpatch
& & &attribute.The shrink wrap optimization is now supported on S/390 and
& & &enabled by default.A major rework of the routines to determine which registers
& & &need to be saved and restored in function prologue/epilogue now
& & &allow to use floating point registers as save slots. &This will
& & &happen for certain leaf function with -march=z10
& & &or higher.The LRA rtl pass replaces reload by default on S/390.RXThe port now allows to specify the RX100, RX200, and RX600 processors
& & &with the command line options -mcpu=rx100, -mcpu=rx200 and -mcpu=rx600.SHMinor improvements to code generated for integer arithmetic and code
& &that involves the T bit.Added support for the SH2A clips and clipu
& &instructions. &The compiler will now try to utilize them for min/max
& &expressions such as max (-128, min (127, x)).Added support for the cmp/str instruction through built-in
& &functions such as __builtin_strlen. &When not optimizing for
& &size, the compiler will now expand calls to e.g. strlen as an
& &inlined sequences which utilize the cmp/str instruction.Improved code generated around volatile memory loads and stores.The option -mcbranchdi has been deprecated. &Specifying it
& &will result in a warning and will not influence code generation.The option -mcmpeqdi has been deprecated. &Specifying it
& &will result in a warning and will not influence code generation.详细内容请看。
GCC 的详细介绍：
GCC 的下载地址：
想通过手机客户端（支持 Android、iPhone 和 Windows Phone）访问开源中国：
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相关讨论话题
你也许会喜欢
倒地还有多少新特性啊
2楼：DarkAngel
C++14 是什么时候出来的？
3楼：leoking 来自
4楼：飛羽灬
谁敢与C++一战？？？？？？
5楼：eechen
Ubuntu 14.04 上的 GCC 是 4.8.2。
6楼：卜库塔
C++貌似认定通过新特性解决以前的旧问题了，还不如甩开包袱出个精简版
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。FreeBSD 是 gcc 4.8.3
8楼：李博文
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。引用来自“冰力”的评论FreeBSD 是 gcc 4.8.3FreeBSD不是换成clang了呗
9楼：李博文
不急，还有个 4.10.x
10楼：pollex
论复杂度，现在的C++完爆任何其他语言几万条街。
11楼：冰力
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。引用来自“冰力”的评论FreeBSD 是 gcc 4.8.3引用来自“李博文”的评论FreeBSD不是换成clang了呗gcc 也可以用，现在 gcc 编译出来的性能跟 clang 差不多了，总是要借鉴的嘛，就是 gcc 自身代码质量臃肿，而且在编译的过程中慢的要死，一个大点的项目开发中，每次编译等很久，浪费开发者时间。
12楼：洪文军
正则好用了没
13楼：zp-wmhx
这个出多厚一本书才可以写清楚这些新特性.?
14楼：李博文
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。引用来自“冰力”的评论FreeBSD 是 gcc 4.8.3引用来自“李博文”的评论FreeBSD不是换成clang了呗引用来自“冰力”的评论gcc 也可以用，现在 gcc 编译出来的性能跟 clang 差不多了，总是要借鉴的嘛，就是 gcc 自身代码质量臃肿，而且在编译的过程中慢的要死，一个大点的项目开发中，每次编译等很久，浪费开发者时间。4.8.3 还没发布吧
15楼：一如当初
新特性，适合自己的就学学，不适合的就别理会。我是这样的。能应付工作就行。
16楼：newzai
g++, 动态数组， lambal 模板。。强悍啊。。功能越来越越强大。
17楼：eechen
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。引用来自“冰力”的评论FreeBSD 是 gcc 4.8.34.8.3还没有发布，你说的应该是4.7.3http://gcc.gnu.org/
18楼：你别逗
14:38 (非会员)
引用来自“eechen”的评论Ubuntu 14.04 上的 GCC 是 4.8.2。引用来自“冰力”的评论FreeBSD 是 gcc 4.8.3引用来自“李博文”的评论FreeBSD不是换成clang了呗引用来自“冰力”的评论gcc 也可以用，现在 gcc 编译出来的性能跟 clang 差不多了，总是要借鉴的嘛，就是 gcc 自身代码质量臃肿，而且在编译的过程中慢的要死，一个大点的项目开发中，每次编译等很久，浪费开发者时间。llvm可以摆上台面，至于clang，呵呵
19楼：中山野鬼
哈，搞这么多年优化，总结一条，该不该优化，优化到什么程度是要解决的重点，而不是优化的策略、方式、方法。
20楼：第五郎
引用来自“中山野鬼”的评论哈，搞这么多年优化，总结一条，该不该优化，优化到什么程度是要解决的重点，而不是优化的策略、方式、方法。还有不该优化的？
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