[LLVMdev] C++ -> C translation problems

Mauro Condarelli MC5686 at mclink.it
Sun Apr 8 09:16:28 PDT 2007

Hi All,
I am trying to use llvm compiler to translate a non-trivial piece of code from C++ to C.
I need this because I need to use part of the code as lib for another project that is strictly C.
I am working under MSWin and I have choice to use either BCC or MSVC.

After a good deal of tries I found out I had to somewhat massage llc -march=c output to make it *almost* compilable.

I have one residual problem I'm unable to overcome :(

I reduced the test program to real minimal version:
class File {
   File() {}
   virtual ~File() {}

class showError : public File {

showError::showError(void) {

showError::~showError(void) {
The acid is the "virtual" specifier in "virtual ~File() {}". If I remove it then BCC32 compiles the resulting program, else it bombs with "Error E2063 terr.c 153: Illegal initialization".

For the whole compilation I use the following .bat file:
rm err.bc
.\..\..\LLVM\bin\llvm-g++ -I../LLVM/include -Wno-deprecated -I../unrar -emit-llvm -c err.cpp -o err.bc
rm err.cbe.c
.\..\..\LLVM\src\llvm-1.9\Release\bin\llc -march=c err.bc

sed "s/!defined(_MSC_VER)/!defined(_MSC_VER) \&\& !defined(__BORLANDC__)/" err.cbe.c >t1

sed "s,__stdcall ,/*__stdcall*/ ,g" t1 >t2
sed "s/_$_/_S_/g" t2 >t3
sed "s/_2$_/_2S_/g" t3 >terr.c
rm t1 t2 t3
"C:\Program Files\Borland\BDS\4.0\bin\bcc32" -I"C:/Program Files/Borland/BDS/4.0/include" -I../unrar -p- -c terr.c

I won't send the (rather long) terr.c, but it is (obviously) available on request.

The offending line is:
/* Global Variable Definitions and Initialization */
vvvvvv this is the culprit vvvvvv
struct l_struct_2E___si_class_type_info_pseudo _ZTI9showError __ATTRIBUTE_WEAK__ = { { ((signed char *)(((unsigned )(&_ZTVN10__cxxabiv120__si_class_type_infoE)) + 8u)), (&(_ZTS9showError[0])) }, ((struct opaque_0 *)(&_ZTI4File)) };
^^^^^^ this is the culprit ^^^^^^
signed char _ZTS9showError[11] __ATTRIBUTE_WEAK__ = "9showError";

I'm using latest stable version (I downloadad it last week).

Also cl doesn't work; first problem is it doesn't like "long long"...


Best Regards

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