From ee841c4d0c10c563c3c34a24b615e9052d98fbb2 Mon Sep 17 00:00:00 2001
From: Martin Quinson <martin.quinson@loria.fr>
Date: Sat, 25 Jul 2015 01:11:05 +0200
Subject: [PATCH] Require g++ v4.7 at least to not speak prehistorical C++

(also: don't install doxygen as we don't build the doc)
---
 .travis.yml                  |  4 +++-
 ChangeLog                    |  1 +
 buildtools/Cmake/Flags.cmake | 15 +++++++--------
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 23ab9f9f6d..364c1450db 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,7 +4,9 @@ compiler:
 #   - clang # does not work for us on debian stable (boost is too old there)
 before_install: 
    - sudo apt-get update  -qq
-   - sudo apt-get install -y cmake doxygen valgrind default-jdk gfortran liblua5.1-dev lua5.1 libboost-dev libboost-all-dev libns3-dev ns3
+   - sudo apt-get install -y g++-4.7 gcc-4.7 cmake valgrind default-jdk gfortran liblua5.1-dev lua5.1 libboost-dev libboost-all-dev libns3-dev ns3
+   - sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.7 50
+   - sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.7 50
 script:
    - cmake -Denable_documentation=OFF -Denable_coverage=OFF -Denable_ns3=ON -Denable_java=ON -Denable_model-checking=OFF -Denable_lua=ON -Denable_compile_optimizations=ON -Denable_smpi=ON -Denable_smpi_MPICH3_testsuite=ON -Denable_compile_warnings=ON . && make && ctest --output-on-failure --timeout 100
 branches:
diff --git a/ChangeLog b/ChangeLog
index c4ab1f6a17..1589b2bdb0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -96,6 +96,7 @@ SimGrid (3.12) NOT RELEASED; urgency=low
    - Add a xbt wrapper for simcall_mutex_trylock (asked in [#17878])
    - Add two new log appenders : rollfile and splitfile. Patch by Fabien Chaix.
  Build System
+  * Require g++ v4.7 at least to not speak prehistorical C++.
   * Tracing is now always enabled (no way to turn it out)
   * Move headers around to sort them out on installed systems:
     - instr/instr.h  -> simgrid/instr.h
diff --git a/buildtools/Cmake/Flags.cmake b/buildtools/Cmake/Flags.cmake
index ccc81bc790..09753b0764 100644
--- a/buildtools/Cmake/Flags.cmake
+++ b/buildtools/Cmake/Flags.cmake
@@ -3,6 +3,12 @@ set(optCFLAGS "")
 
 include(CheckCXXCompilerFlag)
 
+if (CMAKE_COMPILER_IS_GNUCC)
+  if (COMPILER_C_VERSION_MAJOR_MINOR STRLESS "4.7")
+    message(FATAL_ERROR "SimGrid needs g++ version 4.7 to compile.")
+  endif()
+endif()
+
 if(NOT __VISUALC__ AND NOT __BORLANDC__)
   CHECK_CXX_COMPILER_FLAG("-std=gnu++11" HAVE_CXX11)
   CHECK_CXX_COMPILER_FLAG("-std=gnu++0x" HAVE_CXX0X)
@@ -28,13 +34,6 @@ if(enable_compile_warnings)
   set(warnCFLAGS "-fno-common -Wall -Wunused -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wcomment -Wformat -Wwrite-strings -Wno-unused-function -Wno-unused-parameter -Wno-strict-aliasing -Wno-format-nonliteral -Werror ")
   if(CMAKE_COMPILER_IS_GNUCC)
     set(warnCFLAGS "${warnCFLAGS}-Wclobbered -Wno-error=clobbered ")
-    if(COMPILER_C_VERSION_MAJOR_MINOR STRGREATER "4.5")
-      set(warnCFLAGS "${warnCFLAGS}-Wno-error=unused-but-set-variable ")
-    endif()
-    if(COMPILER_C_VERSION_MAJOR_MINOR STREQUAL "4.6")
-    #some old compilers emit bogus warnings here, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=45978 . Avoid failing the build in this case
-      set(warnCFLAGS "${warnCFLAGS}-Wno-error=array-bounds")
-    endif()
   endif()
 
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra  -Wunused -Wpointer-arith -Wchar-subscripts -Wcomment  -Wformat -Wwrite-strings -Wno-unused-function -Wno-unused-parameter -Wno-strict-aliasing -Wno-format-nonliteral -Werror")
@@ -58,7 +57,7 @@ if(enable_compile_optimizations)
       endif()
     else()    
       # On non-windows, 4.6 is enough for that
-      if(COMPILER_C_VERSION_MAJOR_MINOR STRGREATER "4.5" AND LINKER_VERSION STRGREATER "2.22")
+      if(LINKER_VERSION STRGREATER "2.22")
         set(optCFLAGS "${optCFLAGS} -flto ")
       endif()
     endif()
-- 
2.20.1