<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Playground code:</div><div class=""><br class=""></div><div class="">LibCClang startFromRange:(LibCClang defaultRange)</div><div class=""><br class=""></div><div class="">it worked if the resulting struct is not all zeroes.</div><div class=""><br class=""></div><div class="">A tiny C program is the equivalent.</div><div class=""><br class=""></div><div class="">int main()</div><div class="">{</div><div class=""> if(clang_getRangeStart(<span style="font-family: Menlo; font-size: 11px; background-color: rgb(255, 255, 255);" class="">clang_getArbitraryRange</span>()).begin_int_data == 0) printf("That failed\n"); </div><div class=""> else printf("That worked\n")</div><div class=""> return 0;</div><div class="">}</div><div class=""><br class=""></div><br class=""><div><blockquote type="cite" class=""><div class="">On Nov 21, 2017, at 11:18 PM, Ben Coman <<a href="mailto:btc@openinworld.com" class="">btc@openinworld.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class="">Hi Todd,<div class=""><br class=""></div><div class="">Could you advise the the Playground code to use to test this?</div><div class="">And maybe a C program that links to the microclang shared library that does the equivalent test?</div><div class=""><br class=""></div><div class="">cheers -ben<br class=""><div class="gmail_extra"><br class=""><div class="gmail_quote">On 22 November 2017 at 13:38, Todd Blanchard <span dir="ltr" class=""><<a href="mailto:tblanchard@mac.com" target="_blank" class="">tblanchard@mac.com</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <br class=""><div style="word-wrap:break-word" class="">I've been trying to track this down for a couple weeks now.<div class=""><br class=""></div><div class="">I have concluded that structs passed by value to functions on the 64 bit VM are not properly populated. The struct's memory is all zero'd.</div><div class=""><br class=""></div><div class="">I found this while trying to work with LibClang and found that functions that fetched code locations from code ranges always returned invalid zero'd locations. After spending some time with lldb I have traced the problem into the native code and found that the argument is not correct.</div><div class=""><br class=""></div><div class="">I've carved out the wee bit of clang to reproduce this in a tiny library.</div><div class=""><br class=""></div><div class="">The gist of it is below and the entire file is included. Basically the struct passed to the function clang_getRangeStart is zero'd memory regardless of the data I send from the image side.</div><div class=""><br class=""></div><div class="">The build command I used on sierra is <span style="font-family:Menlo;font-size:11px;background-color:rgb(255,255,255)" class="">clang -shared -undefined dynamic_lookup -o microclang.dylib microclang.c</span></div><div class=""><br class=""></div><div class="">I'm stuck. The FFI64 plugin is way beyond my comprehension.</div><div class=""><br class=""></div><div class="">// microclang.c</div><div class=""><br class=""></div><div class=""><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">typedef struct {</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> const void *ptr_data[2];</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> unsigned int_data;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">} CXSourceLocation;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span><br class=""></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">/**</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> * \brief Identifies a half-open character range in the source code.</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> *</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> * Use clang_getRangeStart() and clang_getRangeEnd() to retrieve the</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> * starting and end locations from a source range, respectively.</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> */</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">typedef struct {</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> const void *ptr_data[2];</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> unsigned begin_int_data;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> unsigned end_int_data;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">} CXSourceRange;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span><br class=""></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">const char* first = "first_pointer";</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">const char* second = "second_pointer";</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span><br class=""></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span>// return a fake range with non zero data</div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">CXSourceRange clang_getArbitraryRange()</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">{</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> CXSourceRange range = {0};</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> range.ptr_data[0] = (void*)first;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> range.ptr_data[1] = (void*)second;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> range.begin_int_data = 17;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> range.end_int_data = 24;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> return range;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">}</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span><br class=""></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255);min-height:13px" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""></span>// Actual clang function - range is always zero'd here despite having values in the image</div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">CXSourceLocation clang_getRangeStart(<wbr class="">CXSourceRange range) {</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> // Special decoding for CXSourceLocations for CXLoadedDiagnostics.</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> if ((uintptr_t)range.ptr_data[0] & 0x1) {</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> CXSourceLocation Result = { { range.ptr_data[0], nullptr }, 0 };</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> return Result; </span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> }</span></div><div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; background-color: rgb(255, 255, 255); min-height: 13px;" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> </span><br class="m_-7909243457101396992webkit-block-placeholder"></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> CXSourceLocation Result = { { range.ptr_data[0], range.ptr_data[1] },</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> range.begin_int_data };</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class=""> return Result;</span></div><div style="margin:0px;font-size:11px;line-height:normal;font-family:Menlo;background-color:rgb(255,255,255)" class=""><span style="font-variant-ligatures:no-common-ligatures" class="">}</span></div></div><div class=""><span style="font-variant-ligatures:no-common-ligatures" class=""><br class=""></span></div><div class=""></div></div><br class=""><div style="word-wrap:break-word" class=""><div class=""></div></div><br class=""><div style="word-wrap:break-word" class=""><div class=""></div></div><br class=""></blockquote></div><br class=""></div></div></div>
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