diff options
Diffstat (limited to 'libstdc++-v3/doc/html/manual/bk01pt02ch05s02.html')
| -rw-r--r-- | libstdc++-v3/doc/html/manual/bk01pt02ch05s02.html | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/libstdc++-v3/doc/html/manual/bk01pt02ch05s02.html b/libstdc++-v3/doc/html/manual/bk01pt02ch05s02.html new file mode 100644 index 000000000..6a67bef7c --- /dev/null +++ b/libstdc++-v3/doc/html/manual/bk01pt02ch05s02.html @@ -0,0 +1,50 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"><head><title>Concept Checking</title><meta name="generator" content="DocBook XSL-NS Stylesheets V1.76.1"/><meta name="keywords" content=" ISO C++ , library "/><link rel="home" href="../spine.html" title="The GNU C++ Library"/><link rel="up" href="diagnostics.html" title="Chapter 5. Diagnostics"/><link rel="prev" href="diagnostics.html" title="Chapter 5. Diagnostics"/><link rel="next" href="utilities.html" title="Chapter 6. Utilities"/></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Concept Checking</th></tr><tr><td align="left"><a accesskey="p" href="diagnostics.html">Prev</a> </td><th width="60%" align="center">Chapter 5. + Diagnostics + +</th><td align="right"> <a accesskey="n" href="utilities.html">Next</a></td></tr></table><hr/></div><div class="section" title="Concept Checking"><div class="titlepage"><div><div><h2 class="title"><a id="std.diagnostics.concept_checking"/>Concept Checking</h2></div></div></div><p> + In 1999, SGI added <span class="quote">“<span class="quote">concept checkers</span>”</span> to their + implementation of the STL: code which checked the template + parameters of instantiated pieces of the STL, in order to insure + that the parameters being used met the requirements of the + standard. For example, the Standard requires that types passed as + template parameters to <code class="classname">vector</code> be + "Assignable" (which means what you think it means). The + checking was done during compilation, and none of the code was + executed at runtime. + </p><p> + Unfortunately, the size of the compiler files grew significantly + as a result. The checking code itself was cumbersome. And bugs + were found in it on more than one occasion. + </p><p> + The primary author of the checking code, Jeremy Siek, had already + started work on a replacement implementation. The new code was + formally reviewed and accepted into + <a class="link" href="http://www.boost.org/libs/concept_check/concept_check.htm">the + Boost libraries</a>, and we are pleased to incorporate it into the + GNU C++ library. + </p><p> + The new version imposes a much smaller space overhead on the generated + object file. The checks are also cleaner and easier to read and + understand. + </p><p> + They are off by default for all versions of GCC. + They can be enabled at configure time with + <a class="link" href="configure.html" title="Configure"><code class="literal">--enable-concept-checks</code></a>. + You can enable them on a per-translation-unit basis with + <code class="literal">-D_GLIBCXX_CONCEPT_CHECKS</code>. + </p><p> + Please note that the checks are based on the requirements in the original + C++ standard, some of which have changed in the upcoming C++0x revision. + Additionally, some correct code might be rejected by the concept checks, + for example template argument types may need to be complete when used in + a template definition, rather than at the point of instantiation. + There are no plans to address these shortcomings. + </p></div><div class="navfooter"><hr/><table width="100%" summary="Navigation footer"><tr><td align="left"><a accesskey="p" href="diagnostics.html">Prev</a> </td><td align="center"><a accesskey="u" href="diagnostics.html">Up</a></td><td align="right"> <a accesskey="n" href="utilities.html">Next</a></td></tr><tr><td align="left" valign="top">Chapter 5. + Diagnostics + + </td><td align="center"><a accesskey="h" href="../spine.html">Home</a></td><td align="right" valign="top"> Chapter 6. + Utilities + +</td></tr></table></div></body></html> |