Originally posted by: rumexcrispus

Hi

Can anyone shed some light on this.  I'm on AIX 7.1 with the 13.1.3 version of the xlc and xlC / xlc++ compiler.

I'd like to avoid having to tell cmake where the AIX IBM compiler is using the argument -DCMAKE_C_COMPILER=/opt/IBM/xlc/13.1.3/bin/xlc

The compiler has been installed (following IBM provided media and instructions) to /opt/IBM/xlc/13.1.3/bin.

I have a CMakeLists.txt

with

cmake_minimum_required(VERSION 3.9)
project(cmake-aix)
add_executable(a.out hello.cc)

When I try

cd debug; cmake ..

I see

-- The C compiler identification is XL 13.1.3
-- The CXX compiler identification is XL 13.1.3
CMake Error at /opt/freeware/share/cmake/Modules/Compiler/CMakeCommonCompilerMacros.cmake:42 (message):
  CMAKE_C_STANDARD_COMPUTED_DEFAULT should be set for XL
  (/opt/IBM/xlC/13.1.3/bin/cc) version 13.1.3
Call Stack (most recent call first):
  /opt/freeware/share/cmake/Modules/Compiler/XL-C.cmake:41 (__compiler_check_default_language_standard)
  /opt/freeware/share/cmake/Modules/CMakeCInformation.cmake:25 (include)
  CMakeLists.txt:16 (project)

When I try

cd debug; cmake -DCMAKE_C_COMPILER=/opt/IBM/xlc/13.1.3/bin/xlc   .

cmake does not complain and I can make and run a hello world program successfully.