Two reasons for that:
* the declaration is not used. the LLDB_SOURCE_DIR is provided as the first argument in the script ($1) (called SRC_ROOT in the source code)
* add_custom_command is quoting the first argument of the command. Usually, it is the script itself (and then the full path to the script) but, here, it is the declaration of a variable.
It was failing with:
cd "/llvm-toolchain-3.3~svn179457/build-llvm/tools/lldb/scripts" && "SRCROOT=/llvm-toolchain-3.3~svn179457/tools/lldb" /llvm-toolchain-3.3~svn179457/tools/lldb/scripts/build-swig-wrapper-classes.sh /llvm-toolchain-3.3~svn179457/tools/lldb /llvm-toolchain-3.3~svn179457/build-llvm/tools/lldb/scripts /llvm-toolchain-3.3~svn179457/build-llvm/tools/lldb/scripts /llvm-toolchain-3.3~svn179457/build-llvm -m
/bin/sh: 1: SRCROOT=/llvm-toolchain-3.3~svn179457/tools/lldb: not found
llvm-svn: 179459
DEPENDS ${LLDB_SOURCE_DIR}/scripts/lldb.swig\r
# swig was directly invoked on Windows (where the Python API is not being generated) but on other platforms, we need to run the *swig-wrapper-classes.sh shell-scripts.\r
#COMMAND swig -c++ -shadow -python -I${LLDB_SOURCE_DIR}/include -I./. -outdir ${LLDB_SOURCE_DIR}/scripts/Python -o ${LLDB_SOURCE_DIR}/source/LLDBWrapPython.cpp ${LLDB_SOURCE_DIR}/scripts/lldb.swig\r
- COMMAND SRCROOT=${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/build-swig-wrapper-classes.sh ${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR} -m\r
- COMMAND SRCROOT=${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/finish-swig-wrapper-classes.sh ${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR} -m\r
+ COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/build-swig-wrapper-classes.sh ${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR} -m\r
+ COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/finish-swig-wrapper-classes.sh ${LLDB_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR} -m\r
COMMENT "Building lldb python wrapper")\r
set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/LLDBWrapPython.cpp PROPERTIES GENERATED 1)\r
\r