From 46079d2274de38bd08ea7f731726d1a5a1296b75 Mon Sep 17 00:00:00 2001 From: Brian Gaeke Date: Tue, 21 Oct 2003 21:58:38 +0000 Subject: [PATCH] Add C/C++ build instructions, first draft. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@9355 91177308-0d34-0410-b5e6-96231b3b80d8 --- docs/CFEBuildInstrs.html | 140 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100644 docs/CFEBuildInstrs.html diff --git a/docs/CFEBuildInstrs.html b/docs/CFEBuildInstrs.html new file mode 100644 index 00000000000..3dde111a5df --- /dev/null +++ b/docs/CFEBuildInstrs.html @@ -0,0 +1,140 @@ + +Bootstrapping the C/C++ Front-End + + +

Bootstrapping the C/C++ Front-End

+ +

+ + + +

+Instructions +

This document is intended to explain the process of building the LLVM +C/C++ front-end, based on GCC 3.4, from source.

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.

We welcome patches to help make this process simpler.

Configure and build the LLVM libraries and tools using:
+
```
+ % cd llvm
+ % ./configure [options...]
+ % gmake tools-only
+
```
+
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.
+ +
Add the directory containing the tools to your PATH.
+
```
+ % set path = ( `cd llvm/tools/Debug && pwd` $path )
+
```
+ +
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.
+ +

Make "build" and "install" directories as siblings of the "src" + tree.

+ % pwd
+ /usr/local/example/cfrontend/src
+ % cd ..
+ % mkdir build install
+ % set CFEINSTALL = `pwd`/install
+

+ +

Configure, build and install the C front-end:
+
```
+ % cd build
+ % ../src/configure --prefix=$CFEINSTALL --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 + that LLVM does not support inline assembly. Here are two common + fixes:
+ +
- 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 + $CFEINSTALL/target-triplet/sys-include.
  + +
- Fix 2: If you are building the C++ front-end on a CPU we + haven't tried yet, you will probably have to edit the appropriate + version of atomicity.h under + src/libstdc++-v3/config/cpu/name-of-cpu/atomicity.h + and apply a patch so that it does not use inline assembly.
  +
+ +
Common Problem 2: FIXME: Chris should add a section about + common problems porting to a new architecture, including changes you + might have to make to the gcc/gcc/config/name-of-cpu + directory. For example (expand these):
+ +
- Munge linker flags so they are compatible with gccld. +
- Change the target so it doesn't have long double; just use double + instead. +
- No inline assembly for position independent code. +
- We handle init and fini differently. +
- Do not include inline assembly map things for SPARC, or profile things. +
+ +
Go back into the LLVM source tree proper. Edit Makefile.config +to redefine LLVMGCCDIR to the full pathname of the +$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 +$CFEINSTALL/target-triplet/sys-include to +$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.)
+ +

Build and install the runtime (bytecode) libraries by running:

+ % gmake -C runtime
+ % 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:
+
- compiling and running a "hello, world" program in C or C++. +
- running the tests under test/Programs using gmake -C + test/Programs; +
+ +
+

+ + +

Brian Gaeke

+Last modified: $Date$ + + -- 2.34.1