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<p class="MsoNormal">Hi, Sourabh.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We've confirmed the bug. It can be worked around by removing the VALUE attribute.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can you file an issue for us on the (current) Flang GitHub site?<o:p></o:p></p>
<p class="MsoNormal"><a href="https://github.com/flang-compiler/flang/issues">https://github.com/flang-compiler/flang/issues</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On 3/24/20, 12:52 PM, "flang-dev on behalf of Sourabh Singh Tomar via flang-dev" <<a href="mailto:flang-dev-bounces@lists.llvm.org">flang-dev-bounces@lists.llvm.org</a> on behalf of
<a href="mailto:flang-dev@lists.llvm.org">flang-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:7.5pt;font-family:"Verdana",sans-serif;color:black">External email: Use caution opening links or attachments</span></b><span style="font-size:7.5pt;font-family:"Verdana",sans-serif;color:black">
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<p class="MsoNormal"><o:p> </o:p></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">For a typical Fortran program compiled with flang with -g(debuginfo enabled), I'm noticing *DW_TAG_lexical_block* is getting created as child of the *DW_TAG_subprogram*.<o:p></o:p></p>
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<p class="MsoNormal">As a consequence of this debuggers like GDB is not able to show the arguments of the subprogram.<o:p></o:p></p>
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<p class="MsoNormal">Program snippet -<o:p></o:p></p>
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<p class="MsoNormal">subroutine sub(foo)<br>
integer, value :: foo<br>
print*,foo<br>
end subroutine<br>
program main<br>
interface<br>
subroutine sub(a)<br>
integer, value :: a<br>
end subroutine<br>
end interface<br>
call sub(11)<br>
end program<o:p></o:p></p>
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<p class="MsoNormal">--------------------------------<o:p></o:p></p>
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<p class="MsoNormal">Snippet from GDB --<o:p></o:p></p>
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<p class="MsoNormal">Breakpoint 1, sub () at test.f90:1<br>
1 subroutine sub(foo)<br>
(gdb) info args<br>
No arguments.<o:p></o:p></p>
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<p class="MsoNormal">-----------------------------------<o:p></o:p></p>
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<p class="MsoNormal">Furthermore, *DW_TAG_formal_parameter* is created as a child of this *DW_TAG_lexical_scope*. Hence GDB is showing arguments of the subprogram as locals variables. <o:p></o:p></p>
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<p class="MsoNormal">Snippet DWARF--<o:p></o:p></p>
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<p class="MsoNormal">0x0000002f: DW_TAG_subprogram<o:p></o:p></p>
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<p class="MsoNormal">DW_AT_name ("sub")<o:p></o:p></p>
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<p class="MsoNormal"> DW_AT_low_pc (0x00000000004011b0)<br>
DW_AT_high_pc (0x0000000000401245<br>
.....<br>
0x00000049: DW_TAG_lexical_block<o:p></o:p></p>
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<p class="MsoNormal"> DW_AT_low_pc (0x00000000004011b0)<br>
DW_AT_high_pc (0x0000000000401245<br>
....<br>
0x0000005a: DW_TAG_formal_parameter<o:p></o:p></p>
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<p class="MsoNormal"> DW_AT_name ("foo") <o:p></o:p></p>
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<p class="MsoNormal">0x0000005a: DW_TAG_variable<o:p></o:p></p>
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<p class="MsoNormal"> DW_AT_name ("foo") <o:p></o:p></p>
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<p class="MsoNormal">...<o:p></o:p></p>
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<p class="MsoNormal">---------------------------------------<o:p></o:p></p>
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<p class="MsoNormal">Is this behavior intended ?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Anyone working on this area, Please share your understanding on this!<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">*Please note here that same hierarchy of debug info is also present at LLVM IR level, hence the final DWARF is shared here. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank You,<o:p></o:p></p>
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<p class="MsoNormal">Sourabh.<o:p></o:p></p>
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