configure: Use $CPP instead of cpp directly

The latter breaks in the case of cross-compilation, when `cpp` bears a target prefix.
NixOS · Jan 29, 2018 · f93e890 · f93e890
1 parent 0167eac
commit f93e890
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/configure.ac b/configure.ac
@@ -61,6 +61,7 @@ CFLAGS=
 CXXFLAGS=
 AC_PROG_CC
 AC_PROG_CXX
+AC_PROG_CPP
 AX_CXX_COMPILE_STDCXX_11
 
 
@@ -199,7 +200,7 @@ AC_SUBST(ENABLE_S3, [$enable_s3])
 AC_LANG_POP(C++)
 
 if test -n "$enable_s3"; then
-  declare -a aws_version_tokens=($(printf '#include <aws/core/VersionConfig.h>\nAWS_SDK_VERSION_STRING' | cpp -E | grep -v '^#.*' | sed 's/"//g' | tr '.' ' '))
+  declare -a aws_version_tokens=($(printf '#include <aws/core/VersionConfig.h>\nAWS_SDK_VERSION_STRING' | $CPP - | grep -v '^#.*' | sed 's/"//g' | tr '.' ' '))
   AC_DEFINE_UNQUOTED([AWS_VERSION_MAJOR], ${aws_version_tokens@<:@0@:>@}, [Major version of aws-sdk-cpp.])
   AC_DEFINE_UNQUOTED([AWS_VERSION_MINOR], ${aws_version_tokens@<:@1@:>@}, [Minor version of aws-sdk-cpp.])
 fi