[Mesa-stable] [PATCH 12/17] 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: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: Tomasz Figa <tfiga at chromium.org>
Cc: "17.0" <mesa-stable at lists.freedesktop.org>
Reported-by: Ilia Mirkin <imirkin at alum.mit.edu>
Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
Reviewed-by: Tobias Droste <tdroste at gmx.de>
---
Ilia can you check that it fixes things on your end ?
---
 configure.ac | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/configure.ac b/configure.ac
index 1bdb8a6ed5..469a09e286 100644
--- a/configure.ac
+++ b/configure.ac
@@ -920,16 +920,13 @@ 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 "${LLVM_INCLUDEDIR}/llvm/Config/llvm-config.h"])
@@ -2383,6 +2380,10 @@ dnl
 if test "x$enable_gallium_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