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<base href="https://llvm.org/bugs/" />
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - scan-build: c-cpp-output is incorrect language for compiling pre-processed C (ccache)"
href="https://llvm.org/bugs/show_bug.cgi?id=25851">25851</a>
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<th>Summary</th>
<td>scan-build: c-cpp-output is incorrect language for compiling pre-processed C (ccache)
</td>
</tr>
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<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
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<th>Hardware</th>
<td>PC
</td>
</tr>
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<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
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<th>Component</th>
<td>Static Analyzer
</td>
</tr>
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<th>Assignee</th>
<td>kremenek@apple.com
</td>
</tr>
<tr>
<th>Reporter</th>
<td>d.rigby@me.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr>
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<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>When attempting to run scan-build on Linux against a C codebase where ccache is
being used, clang fails with the following error:
could not find clang line
I've dug into this a bit, and the issue appears to be triggered the fact that
ccache splits the compilation into separate prepress (.c -> .i) followed by
compile (i. -> .o) steps, and ccc-analyzer fails to use the correct language
when compiling a .i file.
See the below test case (along with an annotated ccc-anlayzer) which prints the
arguments passed to clang (['Exec'] and '[Line]' prefixed output):
$ echo "int main() {return 0;}" > foo.i
$ scan-build-3.6 --use-cc=clang-3.6 --use-c++=clang++-3.6 -v gcc -c foo.i -o
foo.o
scan-build: Using '/usr/lib/llvm-3.6/bin/clang' for static analysis
scan-build: Emitting reports for this run to
'/tmp/scan-build-2015-12-16-121345-16395-1'.
[Exec] /usr/lib/llvm-3.6/bin/clang -fsyntax-only -x c-cpp-output foo.i at
/usr/share/clang/scan-build-3.6/ccc-analyzer line 161.
[Line] Ubuntu clang version 3.6.0-2ubuntu1~trusty1 (tags/RELEASE_360/final)
(based on LLVM 3.6.0)
[Line] Target: x86_64-pc-linux-gnu
[Line] Thread model: posix
[Line] clang: error: language not recognized: 'c-cpp-output'
[Line] clang: warning: foo.i: 'linker' input unused
could not find clang line
scan-build: Removing directory '/tmp/scan-build-2015-12-16-121345-16395-1'
because it contains no reports.
scan-build: No bugs found.
Specifically note:
[Line] clang: error: language not recognized: 'c-cpp-output'
The bug appears to be that ccc-analyzer incorrectly uses 'c-cpp-output' for the
name of C-proprocessed source. It should be 'cpp-output'</pre>
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</p>
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