Written by Brian R. Gaeke
+| -Instructions - |
This document is intended to explain the process of building the LLVM -C/C++ front-end, based on GCC 3.4, from source.
+This document is intended to explain the process of building the +LLVM C/C++ front-end, based on GCC 3.4, from its source code. You +would have to do this, for example, if you are porting LLVM to a new +architecture or operating system.
NOTE: This is currently a somewhat fragile, error-prone -process, and you should only try to do it if (A) you really, really, -really can't use the binaries we distribute, and (B) you are a wicked -good GCC hacker.
+process, and you should only try to do it if: + +We welcome patches to help make this process simpler.
+
Configure and build the LLVM libraries and tools using:
@@ -33,17 +62,17 @@ good GCC hacker.
The use of the non-default target "tools-only" means that the
LLVM tools and libraries will build, and the binaries will be
deposited in llvm/tools/Debug, but the runtime (bytecode)
- libraries will not build.
+ libraries will not build.Add the directory containing the tools to your PATH.
- % set path = ( `cd llvm/tools/Debug && pwd` $path ) -+ % set path = ( `cd llvm/tools/Debug && pwd` $path ) +
Unpack the C/C++ front-end source into cfrontend/src.
+Unpack the C/C++ front-end source into cfrontend/src.
Edit src/configure. Change the first line (starting w/ #!) to - contain the correct full pathname of sh.
+ contain the correct full pathname of sh.Make "build" and "install" directories as siblings of the "src" tree.
@@ -53,19 +82,42 @@ good GCC hacker. % cd .. % mkdir build install % set CFEINSTALL = `pwd`/install - +Configure, build, and install the C front-end:
+ ++Linux/x86: +
-Configure, build and install the C front-end:
% cd build
- % ../src/configure --prefix=$CFEINSTALL --disable-nls --disable-shared \
+ % ../src/configure --prefix=$CFEINSTALL --disable-threads --disable-nls --disable-shared \
--enable-languages=c,c++
% gmake all-gcc
% setenv LLVM_LIB_SEARCH_PATH `pwd`/gcc
% gmake all; gmake install
- Common Problem 1: You may get error messages regarding the fact +
+Solaris/Sparc: +
+ ++For Solaris/Sparc, LLVM only supports SparcV9. Therefore, the configure +command line should like something like this: +
+ ++ % cd build + % ../src/configure --prefix=$CFEINSTALL --disable-threads --disable-nls --disable-shared \ + --enable-languages=c,c++ --host=sparcv9-sun-solaris2.8 + % gmake all-gcc + % setenv LLVM_LIB_SEARCH_PATH `pwd`/gcc + % gmake all; gmake install ++ +
Common Problem: You may get error messages regarding the fact that LLVM does not support inline assembly. Here are two common fixes:
@@ -73,34 +125,48 @@ good GCC hacker.Fix 1: If you have system header files that include
inline assembly, you may have to modify them to remove the inline
assembly, and install the modified versions in
- $CFEINSTALL/target-triplet/sys-include.
$CFEINSTALL/target-triplet/sys-include.src/libstdc++-v3/config/cpu/name-of-cpu/atomicity.h
- and apply a patch so that it does not use inline assembly.
+ and apply a patch so that it does not use inline assembly.Common Problem 2: FIXME: Chris should add a section about - common problems porting to a new architecture, including changes you - might have to make to the gcc/gcc/config/name-of-cpu - directory. For example (expand these):
+Porting to a new architecture: If you are porting the new front-end + to a new architecture, or compiling in a different configuration that we have + previously, there are probably several changes you will have to make to the GCC + target to get it to work correctly. These include:
Go back into the LLVM source tree proper. Edit Makefile.config
to redefine LLVMGCCDIR to the full pathname of the
$CFEINSTALL directory, which is the directory you just
installed the C front-end into. (The ./configure script is likely to
-have set this to a directory which does not exist on your system.)
If you edited header files during the C/C++ front-end build as
described in "Fix 1" above, you must now copy those header files from
@@ -108,7 +174,7 @@ described in "Fix 1" above, you must now copy those header files from
$CFEINSTALL/lib/gcc/target-triplet/3.4-llvm/include.
(This should be the "include" directory in the same directory as the
libgcc.a library, which you can find by running
-$CFEINSTALL/bin/gcc --print-libgcc-file-name.)
$CFEINSTALL/bin/gcc --print-libgcc-file-name.)Build and install the runtime (bytecode) libraries by running:
@@ -116,25 +182,29 @@ libgcc.a library, which you can find by running % mkdir $CFEINSTALL/bytecode-libs % gmake -C runtime install % setenv LLVM_LIB_SEARCH_PATH $CFEINSTALL/bytecode-libs -+
Test the newly-installed C frontend by one or more of the following means:
gmake -C
- test/Programs;
+ gmake -C
+ test/Programs