[Qemu-devel] [PATCH] configure: pick the right compiler for OpenBSD by default

["Daniel P. Berrange" <berrange@redhat.com>]

The system compiler in OpenBSD is gcc 4.2.1 which is too
old for our needs. If doing 'pkg_add gcc' you can get a
much newer version (4.9.4 in OpenBSD 6.1) which works with
QEMU. This installs binaries with two naming schemes:

  $ pkg_info  -L gcc | grep bin
  /usr/local/bin/ecpp
  /usr/local/bin/egcc
  /usr/local/bin/egcc-ar
  /usr/local/bin/egcc-nm
  /usr/local/bin/egcc-ranlib
  /usr/local/bin/egcov
  /usr/local/bin/x86_64-unknown-openbsd6.0-egcc
  /usr/local/bin/x86_64-unknown-openbsd6.0-egcc-ar
  /usr/local/bin/x86_64-unknown-openbsd6.0-egcc-nm
  /usr/local/bin/x86_64-unknown-openbsd6.0-egcc-ranlib
  /usr/local/bin/x86_64-unknown-openbsd6.0-gcc-4.9.3

We pick the short name this it won't change across OpenBSD
releases.

This means users don't need to manually pass custom --cc
and --cxx args to configure to avoid immediate failure.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 configure | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/configure b/configure
index 06f18ea9af..fcb7523933 100755
--- a/configure
+++ b/configure
@@ -255,7 +255,21 @@ cross_prefix=""
 audio_drv_list=""
 block_drv_rw_whitelist=""
 block_drv_ro_whitelist=""
-host_cc="cc"
+
+case `uname -s` in
+    OpenBSD)
+    # Default system cc in OpenBSD is unsufficient
+    # we need the 'gcc' pkg added, whch provides
+    # these modified binary names
+    host_cc="egcc"
+    host_cxx="eg++"
+    ;;
+         *)
+    host_cc="cc"
+    host_cxx="c++"
+    ;;
+esac
+
 libs_softmmu=""
 libs_tools=""
 audio_pt_int=""
@@ -466,7 +480,7 @@ else
 fi
 
 if test -z "${CXX}${cross_prefix}"; then
-  cxx="c++"
+  cxx="$host_cxx"
 else
   cxx="${CXX-${cross_prefix}g++}"
 fi
-- 
2.13.5