[Mesa-dev] [PATCH 6/8] configure.ac: set LLVM_{C, CXX, LD}FLAGS only as needed

[Emil Velikov]

From: Emil Velikov <emil.velikov at collabora.com>

Earlier refactoring commits started setting the above regardless if LLVM
is used or not. Move them to the respective section to restore the
original functionality.

Since we require the preprocessor flags (includes in particular) for the
header version parsing keep those as-is. They are not used outside of
configure.ac thus should not cause any side-effects.

As-is adding the C/CXXFLAGS can lead to build issues on when
cross-compiling.

Cc: Tobias Droste <tdroste at gmx.de>
Cc: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: Tomasz Figa <tfiga at chromium.org>
Reported-by: Ilia Mirkin <imirkin at alum.mit.edu>
Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
---
We still want to reworking the C/CPP/CXX sanitazation, but that's
orthogonal to the issue at hand.
---
 configure.ac | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/configure.ac b/configure.ac
index 1ec8e42882..7580fd955f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -971,16 +971,13 @@ strip_unwanted_llvm_flags() {
 llvm_set_environment_variables() {
     if test "x$LLVM_CONFIG" != xno; then
         LLVM_VERSION=`$LLVM_CONFIG --version | egrep -o '^[[0-9.]]+'`
-        LLVM_LDFLAGS=`$LLVM_CONFIG --ldflags`
         LLVM_CPPFLAGS=`strip_unwanted_llvm_flags "$LLVM_CONFIG --cppflags"`
-        LLVM_CFLAGS=$LLVM_CPPFLAGS   # CPPFLAGS seem to be sufficient
-        LLVM_CXXFLAGS=`strip_unwanted_llvm_flags "$LLVM_CONFIG --cxxflags"`
         LLVM_INCLUDEDIR=`$LLVM_CONFIG --includedir`
         LLVM_LIBDIR=`$LLVM_CONFIG --libdir`
 
-        # We need to respect LLVM_CFLAGS when compiling LLVM headers.
+        # We need to respect LLVM_CPPFLAGS when compiling LLVM headers.
         save_CFLAGS="$CFLAGS"
-        CFLAGS="$CFLAGS $LLVM_CFLAGS"
+        CFLAGS="$CFLAGS $LLVM_CPPFLAGS"
 
         AC_COMPUTE_INT([LLVM_VERSION_MAJOR], [LLVM_VERSION_MAJOR],
             [#include "${LLVM_INCLUDEDIR}/llvm/Config/llvm-config.h"])
@@ -2584,6 +2581,10 @@ dnl Set HAVE_LLVM compiler define if LLVM is used.
 if test "x$USE_LLVM" = xyes; then
     DEFINES="${DEFINES} -DHAVE_LLVM=0x0$LLVM_VERSION_INT -DMESA_LLVM_VERSION_PATCH=$LLVM_VERSION_PATCH"
 
+    LLVM_LDFLAGS=`$LLVM_CONFIG --ldflags`
+    LLVM_CFLAGS=$LLVM_CPPFLAGS   # CPPFLAGS seem to be sufficient
+    LLVM_CXXFLAGS=`strip_unwanted_llvm_flags "$LLVM_CONFIG --cxxflags"`
+
     dnl Set LLVM_LIBS - This is done after the driver configuration so
     dnl that drivers can add additional components to LLVM_COMPONENTS.
     dnl Previously, gallium drivers were updating LLVM_LIBS directly
-- 
2.11.0