llvmpipe: Only get the preprocessor flags from llvm-config.
Otherwise we get -O2 optimization flag, preventing proper debugging.
diff --git a/src/gallium/drivers/llvmpipe/SConscript b/src/gallium/drivers/llvmpipe/SConscript
index 71e4e6a..aca4f21 100644
--- a/src/gallium/drivers/llvmpipe/SConscript
+++ b/src/gallium/drivers/llvmpipe/SConscript
@@ -2,7 +2,7 @@
env = env.Clone()
-env.ParseConfig('llvm-config --cflags')
+env.ParseConfig('llvm-config --cppflags')
llvmpipe = env.ConvenienceLibrary(
target = 'llvmpipe',