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diff --git a/share/doc/gccint/Test-Idioms.html b/share/doc/gccint/Test-Idioms.html new file mode 100644 index 0000000..a122a9b --- /dev/null +++ b/share/doc/gccint/Test-Idioms.html @@ -0,0 +1,164 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). A copy of the license is included in the section entitled +"GNU Free Documentation License". + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>GNU Compiler Collection (GCC) Internals: Test Idioms</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Test Idioms"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Test Idioms"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Testsuites.html#Testsuites" rel="up" title="Testsuites"> +<link href="Test-Directives.html#Test-Directives" rel="next" title="Test Directives"> +<link href="Testsuites.html#Testsuites" rel="previous" title="Testsuites"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Test-Idioms"></a> +<div class="header"> +<p> +Next: <a href="Test-Directives.html#Test-Directives" accesskey="n" rel="next">Test Directives</a>, Up: <a href="Testsuites.html#Testsuites" accesskey="u" rel="up">Testsuites</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Idioms-Used-in-Testsuite-Code"></a> +<h3 class="section">7.1 Idioms Used in Testsuite Code</h3> + +<p>In general, C testcases have a trailing <samp>-<var>n</var>.c</samp>, starting +with <samp>-1.c</samp>, in case other testcases with similar names are added +later. If the test is a test of some well-defined feature, it should +have a name referring to that feature such as +<samp><var>feature</var>-1.c</samp>. If it does not test a well-defined feature +but just happens to exercise a bug somewhere in the compiler, and a +bug report has been filed for this bug in the GCC bug database, +<samp>pr<var>bug-number</var>-1.c</samp> is the appropriate form of name. +Otherwise (for miscellaneous bugs not filed in the GCC bug database), +and previously more generally, test cases are named after the date on +which they were added. This allows people to tell at a glance whether +a test failure is because of a recently found bug that has not yet +been fixed, or whether it may be a regression, but does not give any +other information about the bug or where discussion of it may be +found. Some other language testsuites follow similar conventions. +</p> +<p>In the <samp>gcc.dg</samp> testsuite, it is often necessary to test that an +error is indeed a hard error and not just a warning—for example, +where it is a constraint violation in the C standard, which must +become an error with <samp>-pedantic-errors</samp>. The following idiom, +where the first line shown is line <var>line</var> of the file and the line +that generates the error, is used for this: +</p> +<div class="smallexample"> +<pre class="smallexample">/* { dg-bogus "warning" "warning in place of error" } */ +/* { dg-error "<var>regexp</var>" "<var>message</var>" { target *-*-* } <var>line</var> } */ +</pre></div> + +<p>It may be necessary to check that an expression is an integer constant +expression and has a certain value. To check that <code><var>E</var></code> has +value <code><var>V</var></code>, an idiom similar to the following is used: +</p> +<div class="smallexample"> +<pre class="smallexample">char x[((E) == (V) ? 1 : -1)]; +</pre></div> + +<p>In <samp>gcc.dg</samp> tests, <code>__typeof__</code> is sometimes used to make +assertions about the types of expressions. See, for example, +<samp>gcc.dg/c99-condexpr-1.c</samp>. The more subtle uses depend on the +exact rules for the types of conditional expressions in the C +standard; see, for example, <samp>gcc.dg/c99-intconst-1.c</samp>. +</p> +<p>It is useful to be able to test that optimizations are being made +properly. This cannot be done in all cases, but it can be done where +the optimization will lead to code being optimized away (for example, +where flow analysis or alias analysis should show that certain code +cannot be called) or to functions not being called because they have +been expanded as built-in functions. Such tests go in +<samp>gcc.c-torture/execute</samp>. Where code should be optimized away, a +call to a nonexistent function such as <code>link_failure ()</code> may be +inserted; a definition +</p> +<div class="smallexample"> +<pre class="smallexample">#ifndef __OPTIMIZE__ +void +link_failure (void) +{ + abort (); +} +#endif +</pre></div> + +<p>will also be needed so that linking still succeeds when the test is +run without optimization. When all calls to a built-in function +should have been optimized and no calls to the non-built-in version of +the function should remain, that function may be defined as +<code>static</code> to call <code>abort ()</code> (although redeclaring a function +as static may not work on all targets). +</p> +<p>All testcases must be portable. Target-specific testcases must have +appropriate code to avoid causing failures on unsupported systems; +unfortunately, the mechanisms for this differ by directory. +</p> +<p>FIXME: discuss non-C testsuites here. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Test-Directives.html#Test-Directives" accesskey="n" rel="next">Test Directives</a>, Up: <a href="Testsuites.html#Testsuites" accesskey="u" rel="up">Testsuites</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |