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<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Hi Enrique,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">First error is occurred because default OpenCL C version is 1.0 (or 1.1) and it doesn’t support double precision floating point types. If the target hardware supports doubles, the error
can be fixed by either enable `cl_khr_fp64` extension support (-cl-ext=-cl_khr_fp64) or by setting OpenCL C version to 1.2 (-cl-std=CL1.2).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US">'../Programs/kernels/longest/longest_0038.cl:28:19: warning: incompatible pointer to integer conversion initializing 'const __private int' with an expression of type '__global int *' [-Wint-conversion]<br>
const int v = a + f * 2 + l % v;'<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">This warning says that “a + f * 2 + l %v;” expression has `__global int *` type i.e. global address space pointer and assigning it to integer value is not safe. This looks like a bug
in the code. One of the variables in the expression (`a`?) is a pointer, which probably should be dereferenced (*a or a[id]).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Also, I would use the driver to compile OpenCL code (i.e. invoke clang without `-cc1` option) if you don’t have reasons to use the front-end.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">User’s Manual covers most of the OpenCL options:
</span><a href="https://clang.llvm.org/docs/UsersManual.html#opencl-features"><span lang="EN-US">https://clang.llvm.org/docs/UsersManual.html#opencl-features</span></a><span lang="EN-US">.</span><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US">Alexey<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> cfe-dev <cfe-dev-bounces@lists.llvm.org>
<b>On Behalf Of </b>Enrique Gonzalez via cfe-dev<br>
<b>Sent:</b> Tuesday, May 12, 2020 2:41 PM<br>
<b>To:</b> cfe-dev@lists.llvm.org<br>
<b>Subject:</b> [cfe-dev] Clang OpenCL errors and warnings<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal">Hello everyone,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I am using Clang 11 for an OpenCL-SPIRV project. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">When I try to convert some OpenCL programs into bytecode, I receive the following error message in some of them:<o:p></o:p></p>
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<p class="MsoNormal">'../Programs/kernels/longest/longest_0038.cl:19:5: error: use of type 'double' requires cl_khr_fp64 extension to be enabled<br>
double const t = 2 * (h + 2);'<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Also, I receive some warnings like: <o:p></o:p></p>
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<p class="MsoNormal">'../Programs/kernels/longest/longest_0038.cl:28:19: warning: incompatible pointer to integer conversion initializing 'const __private int' with an expression of type '__global int *' [-Wint-conversion]<br>
const int v = a + f * 2 + l % v;'<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">This OpenCL codes are automatically generated by a tool called "clgen" from github, that I am using as my OpenCL source code database.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">This errors and warnings are given because the code is not well written or because I need to use more flags in my clang command?
<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I use this command to convert OpenCL programs into bytecode:<o:p></o:p></p>
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<p class="MsoNormal">'clang -cc1 -triple spir64 -emit-llvm-bc -finclude-default-header -cl-single-precision-constant -disable-llvm-passes INPUT.cl -o INPUT.bc'<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks in advance.<o:p></o:p></p>
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