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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi, <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I came across this behavior irregularity in LLVM for ARM backend (-target arm-linux-gnueabi) with the constant promotion optimization in arm (-arm-promote-constant=true). <o:p></o:p></p><p class=MsoNormal>For the attached source files compiling with the following:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>clang++ -target arm-linux-gnueabi A.cpp B.cpp –o a.out<o:p></o:p></p><p class=MsoNormal>The addresses returned from bar() and foo() are not the same (string literals live in different memory locations) however, when we turn off the constant pool optimization<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>clang-arm-x++ -Ofast -mllvm -arm-promote-constant=false A.cpp B.cpp -o test_case.exe –o a.out <o:p></o:p></p><p class=MsoNormal>we are getting the same addresses for string literals.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Looking into the ll files , the strings are created as “private unnamed_addr constant” so the constant pool optimization pass is promoting them to constant pools and causing them to have different addresses, which seems fine.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is this behavior in line with the C++ standard for strings in extern inline functions? If not, what should be the correct linkage type emitted for this constant? Is this a potential clang bug?<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><p class=MsoNormal><o:p> </o:p></p></div></body></html>