[libcxx] fix cxx-benchmarks target compilation

[ivafanas]

Summary

Proposal to fix command

make cxx-benchmarks

Now it produces the following error:

/home/ivafanas/Documents/clang/cl/llvm-project/libcxx/benchmarks/string.bench.cpp:78:32: error: inlining failed in call to always_inline ‘const char* getSmallString(DiffType)’: function body can be overwritten at link time
 TEST_ALWAYS_INLINE const char* getSmallString(DiffType D) {

[ldionne]

make cxx-benchmarks work for me, can you please explain what compiler you're using and exactly how you get the error?

[ivafanas]

In D64515#1580721, @ldionne wrote:

make cxx-benchmarks work for me, can you please explain what compiler you're using and exactly how you get the error?

Hi,

I use this:

mkdir cl2
cd cl2
git clone https://github.com/llvm/llvm-project.git 
cd llvm-project
mkdir build_release
cd build_release
cmake -DLLVM_ENABLE_PROJECTS="clang;libcxx;libcxxabi" -DCMAKE_BUILD_TYPE=Release ../llvm
make cxx-benchmarks

After your question I've re-checked compiler using make VERBOSE=1 cxx-benchmarks command and it is g++ 7.4.0.

Seems like fix is irrelevant to clang. Sorry for the false report.

libcxx/benchmarks/string.bench.cpp

 enum class DiffType { Control, ChangeFirst, ChangeMiddle, ChangeLast };
 struct AllDiffTypes : EnumValuesAsTuple<AllDiffTypes, DiffType, 4> {
   static constexpr const char* Names[] = {"Control", "ChangeFirst",
                                           "ChangeMiddle", "ChangeLast"};
 };
 
 static constexpr char SmallStringLiteral[] = "012345678";
 
-TEST_ALWAYS_INLINE const char* getSmallString(DiffType D) {
+inline TEST_ALWAYS_INLINE const char* getSmallString(DiffType D) {
   switch (D) {
     case DiffType::Control:
       return SmallStringLiteral;
     case DiffType::ChangeFirst:
       return "-12345678";
     case DiffType::ChangeMiddle:
       return "0123-5678";
     case DiffType::ChangeLast:
       return "01234567-";
   }
 }
 
 static constexpr char LargeStringLiteral[] =
     "012345678901234567890123456789012345678901234567890123456789012";
 
-TEST_ALWAYS_INLINE const char* getLargeString(DiffType D) {
+inline TEST_ALWAYS_INLINE const char* getLargeString(DiffType D) {
 #define LARGE_STRING_FIRST "123456789012345678901234567890"
 #define LARGE_STRING_SECOND "234567890123456789012345678901"
   switch (D) {
     case DiffType::Control:
       return "0" LARGE_STRING_FIRST "1" LARGE_STRING_SECOND "2";
     case DiffType::ChangeFirst:
       return "-" LARGE_STRING_FIRST "1" LARGE_STRING_SECOND "2";
     case DiffType::ChangeMiddle:
       return "0" LARGE_STRING_FIRST "-" LARGE_STRING_SECOND "2";
     case DiffType::ChangeLast:
       return "0" LARGE_STRING_FIRST "1" LARGE_STRING_SECOND "-";
   }
 }
 
-TEST_ALWAYS_INLINE const char* getHugeString(DiffType D) {
+inline TEST_ALWAYS_INLINE const char* getHugeString(DiffType D) {
 #define HUGE_STRING0 "0123456789"
 #define HUGE_STRING1 HUGE_STRING0 HUGE_STRING0 HUGE_STRING0 HUGE_STRING0
 #define HUGE_STRING2 HUGE_STRING1 HUGE_STRING1 HUGE_STRING1 HUGE_STRING1
 #define HUGE_STRING3 HUGE_STRING2 HUGE_STRING2 HUGE_STRING2 HUGE_STRING2
 #define HUGE_STRING4 HUGE_STRING3 HUGE_STRING3 HUGE_STRING3 HUGE_STRING3
   switch (D) {
     case DiffType::Control:
       return "0123456789" HUGE_STRING4 "0123456789" HUGE_STRING4 "0123456789";
     case DiffType::ChangeFirst:
       return "-123456789" HUGE_STRING4 "0123456789" HUGE_STRING4 "0123456789";
     case DiffType::ChangeMiddle:
       return "0123456789" HUGE_STRING4 "01234-6789" HUGE_STRING4 "0123456789";
     case DiffType::ChangeLast:
       return "0123456789" HUGE_STRING4 "0123456789" HUGE_STRING4 "012345678-";
   }
 }
 
+inline
 TEST_ALWAYS_INLINE std::string makeString(Length L,
                                           DiffType D = DiffType::Control,
                                           Opacity O = Opacity::Transparent) {
   switch (L) {
   case Length::Empty:
     return maybeOpaque("", O == Opacity::Opaque);
   case Length::Small:
     return maybeOpaque(getSmallString(D), O == Opacity::Opaque);