Allow setting, archiver, C compiler flags and linker flags from commandline (#549)

- Read Fortran compiler from FPM_FC or --compiler (deprecate FPM_COMPILER)
- Read Fortran compiler options from FPM_FFLAGS or --flag
- Read C compiler from FPM_CC or --c-compiler (deprecate FPM_C_COMPILER)
- Read C compiler options from FPM_CFLAGS or --c-flag
- Read archiver from FPM_AR or --archiver
- Read linker options from FPM_LDFLAGS or --link-flag

5 files changed, 197 insertions, 93 deletions

diff --git a/src/fpm.f90 b/src/fpm.f90
index 1449dc2..d8381ae 100644
--- a/src/fpm.f90
+++ b/src/fpm.f90
@@ -39,7 +39,7 @@ subroutine build_model(model, settings, package, error)
 
     integer :: i, j
     type(package_config_t) :: dependency
-    character(len=:), allocatable :: manifest, lib_dir, flags
+    character(len=:), allocatable :: manifest, lib_dir, flags, cflags, ldflags
 
     logical :: duplicates_found = .false.
     type(string_t) :: include_dir
@@ -60,8 +60,8 @@ subroutine build_model(model, settings, package, error)
       call filewrite(join_path("build", ".gitignore"),["*"])
     end if
 
-    call new_compiler(model%compiler, settings%compiler)
-    call new_archiver(model%archiver)
+    call new_compiler(model%compiler, settings%compiler, settings%c_compiler)
+    call new_archiver(model%archiver, settings%archiver)
 
     if (settings%flag == '') then
         flags = model%compiler%get_default_flags(settings%profile == "release")
@@ -73,7 +73,10 @@ subroutine build_model(model, settings, package, error)
         end select
     end if
 
-    write(build_name, '(z16.16)') fnv_1a(flags)
+    cflags = trim(settings%cflag)
+    ldflags = trim(settings%ldflag)
+
+    write(build_name, '(z16.16)') fnv_1a(flags//cflags//ldflags)
 
     if (model%compiler%is_unknown()) then
         write(*, '(*(a:,1x))') &
@@ -197,6 +200,8 @@ subroutine build_model(model, settings, package, error)
         write(*,*)'<INFO> COMPILER:  ',model%compiler%fc
         write(*,*)'<INFO> C COMPILER:  ',model%compiler%cc
         write(*,*)'<INFO> COMPILER OPTIONS:  ', model%fortran_compile_flags
+        write(*,*)'<INFO> C COMPILER OPTIONS:  ', model%c_compile_flags
+        write(*,*)'<INFO> LINKER OPTIONS:  ', model%link_flags
         write(*,*)'<INFO> INCLUDE DIRECTORIES:  [', string_cat(model%include_dirs,','),']'
      end if
 
diff --git a/src/fpm_command_line.f90 b/src/fpm_command_line.f90
index c646e4a..df27695 100644
--- a/src/fpm_command_line.f90
+++ b/src/fpm_command_line.f90
@@ -69,8 +69,12 @@ type, extends(fpm_cmd_settings)  :: fpm_build_settings
     logical                      :: show_model=.false.
     logical                      :: build_tests=.false.
     character(len=:),allocatable :: compiler
+    character(len=:),allocatable :: c_compiler
+    character(len=:),allocatable :: archiver
     character(len=:),allocatable :: profile
     character(len=:),allocatable :: flag
+    character(len=:),allocatable :: cflag
+    character(len=:),allocatable :: ldflag
 end type
 
 type, extends(fpm_build_settings)  :: fpm_run_settings
@@ -112,7 +116,53 @@ character(len=20),parameter :: manual(*)=[ character(len=20) ::&
 &  ' ',     'fpm',     'new',   'build',  'run',     &
 &  'test',  'runner', 'install', 'update', 'list',   'help',   'version'  ]
 
-character(len=:), allocatable :: val_runner, val_compiler, val_flag, val_profile
+character(len=:), allocatable :: val_runner, val_compiler, val_flag, val_cflag, val_ldflag, &
+    val_profile
+
+character(len=80), parameter :: help_text_compiler(*) = [character(len=80) :: &
+    ' --compiler NAME   Specify a compiler name. The default is "gfortran"',&
+    '                   unless set by the environment variable FPM_FC.',&
+    ' --c-compiler NAME Specify the C compiler name. By default automatic determined',&
+    '                   unless set by the environment variable FPM_CC.',&
+    ' --archiver NAME   Specify the archiver name. By default automatic determined',&
+    '                   unless set by the environment variable FPM_AR.'&
+    ]
+
+character(len=80), parameter :: help_text_flag(*) = [character(len=80) :: &
+    ' --flag  FFLAGS    selects compile arguments for the build, the default',&
+    '                   value is set by the FPM_FFLAGS environment variable.', &
+    '                   These are added to the profile options if --profile', &
+    '                   is specified, else these options override the defaults.',&
+    '                   Note object and .mod directory locations are always',&
+    '                   built in.',&
+    ' --c-flag CFLAGS   selects compile arguments specific for C source in the build.',&
+    '                   The default value is set by the FPM_CFLAGS environment variable.',&
+    ' --link-flag LDFLAGS',&
+    '                   select arguments passed to the linker for the build.',&
+    '                   The default value is set by the FPM_LDFLAGS environment variable.'&
+    ]
+
+
+character(len=80), parameter :: help_text_environment(*) = [character(len=80) :: &
+    'ENVIRONMENT VARIABLES',&
+    ' FPM_FC            sets the path to the Fortran compiler used for the build,', &
+    '                   will be overwritten by --compiler command line option', &
+    '', &
+    ' FPM_FFLAGS        sets the arguments for the Fortran compiler', &
+    '                   will be overwritten by --flag command line option', &
+    '', &
+    ' FPM_CC            sets the path to the C compiler used for the build,', &
+    '                   will be overwritten by --c-compiler command line option', &
+    '', &
+    ' FPM_CFLAGS        sets the arguments for the C compiler', &
+    '                   will be overwritten by --c-flag command line option', &
+    '', &
+    ' FPM_AR            sets the path to the archiver used for the build,', &
+    '                   will be overwritten by --archiver command line option', &
+    '', &
+    ' FPM_LDFLAGS       sets additional link arguments for creating executables', &
+    '                   will be overwritten by --link-flag command line option' &
+    ]
 
 contains
     subroutine get_command_line_settings(cmd_settings)
@@ -122,7 +172,12 @@ contains
         integer                       :: i
         integer                       :: widest
         type(fpm_install_settings), allocatable :: install_settings
-        character(len=:), allocatable :: common_args, working_dir
+        character(len=:), allocatable :: common_args, compiler_args, run_args, working_dir, &
+            & c_compiler, archiver
+
+        character(len=*), parameter :: fc_env = "FC", cc_env = "CC", ar_env = "AR", &
+            & fflags_env = "FFLAGS", cflags_env = "CFLAGS", ldflags_env = "LDFLAGS", &
+            & fc_default = "gfortran", cc_default = " ", ar_default = " ", flags_default = " "
 
         call set_help()
         ! text for --version switch,
@@ -149,23 +204,32 @@ contains
         CLI_RESPONSE_FILE=.true.
         cmdarg = get_subcommand()
 
-        common_args = '--directory:C " " '
+        common_args = &
+          ' --directory:C " "' // &
+          ' --verbose F'
+
+        run_args = &
+          ' --target " "' // &
+          ' --list F' // &
+          ' --runner " "'
+
+        compiler_args = &
+          ' --profile " "' // &
+          ' --compiler "'//get_fpm_env(fc_env, fc_default)//'"' // &
+          ' --c-compiler "'//get_fpm_env(cc_env, cc_default)//'"' // &
+          ' --archiver "'//get_fpm_env(ar_env, ar_default)//'"' // &
+          ' --flag:: "'//get_fpm_env(fflags_env, flags_default)//'"' // &
+          ' --c-flag:: "'//get_fpm_env(cflags_env, flags_default)//'"' // &
+          ' --link-flag:: "'//get_fpm_env(ldflags_env, flags_default)//'"'
 
         ! now set subcommand-specific help text and process commandline
         ! arguments. Then call subcommand routine
         select case(trim(cmdarg))
 
         case('run')
-            call set_args(common_args //'&
-            & --target " " &
-            & --list F &
+            call set_args(common_args // compiler_args // run_args //'&
             & --all F &
-            & --profile " "&
             & --example F&
-            & --runner " " &
-            & --compiler "'//get_env('FPM_COMPILER','gfortran')//'" &
-            & --flag:: " "&
-            & --verbose F&
             & --',help_run,version_text)
 
             call check_build_vals()
@@ -193,6 +257,8 @@ contains
                if(names(i).eq.'..')names(i)='*'
             enddo
 
+            c_compiler = sget('c-compiler')
+            archiver = sget('archiver')
             allocate(fpm_run_settings :: cmd_settings)
             val_runner=sget('runner')
             if(specified('runner') .and. val_runner.eq.'')val_runner='echo'
@@ -200,7 +266,11 @@ contains
             & args=remaining,&
             & profile=val_profile,&
             & compiler=val_compiler, &
+            & c_compiler=c_compiler, &
+            & archiver=archiver, &
             & flag=val_flag, &
+            & cflag=val_cflag, &
+            & ldflag=val_ldflag, &
             & example=lget('example'), &
             & list=lget('list'),&
             & build_tests=.false.,&
@@ -209,23 +279,25 @@ contains
             & verbose=lget('verbose') )
 
         case('build')
-            call set_args(common_args // '&
-            & --profile " " &
+            call set_args(common_args // compiler_args //'&
             & --list F &
             & --show-model F &
-            & --compiler "'//get_env('FPM_COMPILER','gfortran')//'" &
-            & --flag:: " "&
             & --tests F &
-            & --verbose F &
             & --',help_build,version_text)
 
             call check_build_vals()
 
+            c_compiler = sget('c-compiler')
+            archiver = sget('archiver')
             allocate( fpm_build_settings :: cmd_settings )
             cmd_settings=fpm_build_settings(  &
             & profile=val_profile,&
             & compiler=val_compiler, &
+            & c_compiler=c_compiler, &
+            & archiver=archiver, &
             & flag=val_flag, &
+            & cflag=val_cflag, &
+            & ldflag=val_ldflag, &
             & list=lget('list'),&
             & show_model=lget('show-model'),&
             & build_tests=lget('tests'),&
@@ -240,8 +312,7 @@ contains
             & --example F &
             & --backfill F &
             & --full F &
-            & --bare F &
-            & --verbose:V F',&
+            & --bare F', &
             & help_new, version_text)
             select case(size(unnamed))
             case(1)
@@ -300,9 +371,7 @@ contains
             endif
 
         case('help','manual')
-            call set_args(common_args // '&
-            & --verbose F &
-            & ',help_help,version_text)
+            call set_args(common_args, help_help,version_text)
             if(size(unnamed).lt.2)then
                 if(unnamed(1).eq.'help')then
                    unnamed=['   ', 'fpm']
@@ -348,22 +417,26 @@ contains
             call printhelp(help_text)
 
         case('install')
-            call set_args(common_args // '&
-                & --profile " " --no-rebuild F --verbose F --prefix " " &
+            call set_args(common_args // compiler_args // '&
+                & --no-rebuild F --prefix " " &
                 & --list F &
-                & --compiler "'//get_env('FPM_COMPILER','gfortran')//'" &
-                & --flag:: " "&
                 & --libdir "lib" --bindir "bin" --includedir "include"', &
                 help_install, version_text)
 
             call check_build_vals()
 
+            c_compiler = sget('c-compiler')
+            archiver = sget('archiver')
             allocate(install_settings)
             install_settings = fpm_install_settings(&
                 list=lget('list'), &
                 profile=val_profile,&
                 compiler=val_compiler, &
+                c_compiler=c_compiler, &
+                archiver=archiver, &
                 flag=val_flag, &
+                cflag=val_cflag, &
+                ldflag=val_ldflag, &
                 no_rebuild=lget('no-rebuild'), &
                 verbose=lget('verbose'))
             call get_char_arg(install_settings%prefix, 'prefix')
@@ -375,22 +448,14 @@ contains
         case('list')
             call set_args(common_args // '&
             & --list F&
-            & --verbose F&
             &', help_list, version_text)
             call printhelp(help_list_nodash)
             if(lget('list'))then
                call printhelp(help_list_dash)
             endif
         case('test')
-            call set_args(common_args // '&
-            & --target " " &
-            & --list F&
-            & --profile " "&
-            & --runner " " &
-            & --compiler "'//get_env('FPM_COMPILER','gfortran')//'" &
-            & --flag:: " "&
-            & --verbose F&
-            & --',help_test,version_text)
+            call set_args(common_args // compiler_args // run_args // ' --', &
+              help_test,version_text)
 
             call check_build_vals()
 
@@ -411,6 +476,8 @@ contains
                if(names(i).eq.'..')names(i)='*'
             enddo
 
+            c_compiler = sget('c-compiler')
+            archiver = sget('archiver')
             allocate(fpm_test_settings :: cmd_settings)
             val_runner=sget('runner')
             if(specified('runner') .and. val_runner.eq.'')val_runner='echo'
@@ -418,7 +485,11 @@ contains
             & args=remaining, &
             & profile=val_profile, &
             & compiler=val_compiler, &
+            & c_compiler=c_compiler, &
+            & archiver=archiver, &
             & flag=val_flag, &
+            & cflag=val_cflag, &
+            & ldflag=val_ldflag, &
             & example=.false., &
             & list=lget('list'), &
             & build_tests=.true., &
@@ -427,7 +498,7 @@ contains
             & verbose=lget('verbose') )
 
         case('update')
-            call set_args(common_args // ' --fetch-only F --verbose F --clean F', &
+            call set_args(common_args // ' --fetch-only F --clean F', &
                 help_update, version_text)
 
             if( size(unnamed) .gt. 1 )then
@@ -448,7 +519,6 @@ contains
             else
                 call set_args('&
                 & --list F&
-                & --verbose F&
                 &', help_fpm, version_text)
                 ! Note: will not get here if --version or --usage or --help
                 ! is present on commandline
@@ -485,6 +555,8 @@ contains
         endif
 
         val_flag = " " // sget('flag')
+        val_cflag = " " // sget('c-flag')
+        val_ldflag = " " // sget('link-flag')
         val_profile = sget('profile')
 
     end subroutine check_build_vals
@@ -665,16 +737,11 @@ contains
     '                   high optimization and "debug" for full debug options.',&
     '                   If --flag is not specified the "debug" flags are the',&
     '                   default. ',&
-    ' --flag  FFLAGS    selects compile arguments for the build. These are',&
-    '                   added to the profile options if --profile is specified,',&
-    '                   else these options override the defaults.',&
-    '                   Note object and .mod directory locations are always',&
-    '                   built in.',&
+    help_text_compiler, &
+    help_text_flag, &
     '  --list     List candidates instead of building or running them. On   ', &
     '             the fpm(1) command this shows a brief list of subcommands.', &
     '  --runner CMD   Provides a command to prefix program execution paths. ', &
-    '  --compiler COMPILER_NAME  Compiler name. The environment variable    ', &
-    '                            FPM_COMPILER sets the default.             ', &
     '  -- ARGS    Arguments to pass to executables.                         ', &
     '                                                                       ', &
     'VALID FOR ALL SUBCOMMANDS                                              ', &
@@ -713,6 +780,8 @@ contains
     '   (currently) allow for continued lines or multiple specifications of ', &
     '   the same option.                                                    ', &
     '                                                                       ', &
+    help_text_environment, &
+    '                                                                       ', &
     'EXAMPLES                                                               ', &
     '   sample commands:                                                    ', &
     '                                                                       ', &
@@ -790,14 +859,8 @@ contains
     '                   high optimization and "debug" for full debug options.',&
     '                   If --flag is not specified the "debug" flags are the',&
     '                   default. ',&
-    ' --flag  FFLAGS    selects compile arguments for the build. These are',&
-    '                   added to the profile options if --profile is specified,',&
-    '                   else these options override the defaults.',&
-    '                   Note object and .mod directory locations are always',&
-    '                   built in.',&
-    ' --compiler COMPILER_NAME  Specify a compiler name. The default is     ', &
-    '                           "gfortran" unless set by the environment    ', &
-    '                           variable FPM_COMPILER.                      ', &
+    help_text_compiler, &
+    help_text_flag, &
     ' --runner CMD  A command to prefix the program execution paths with.   ', &
     '               see "fpm help runner" for further details.              ', &
     ' --list     list pathname of candidates instead of running them. Note  ', &
@@ -806,6 +869,8 @@ contains
     ' -- ARGS    optional arguments to pass to the program(s). The same     ', &
     '            arguments are passed to all program names specified.       ', &
     '                                                                       ', &
+    help_text_environment, &
+    '                                                                       ', &
     'EXAMPLES                                                               ', &
     ' fpm(1) - run or display project applications:                         ', &
     '                                                                       ', &
@@ -863,20 +928,16 @@ contains
     '                   high optimization and "debug" for full debug options.',&
     '                   If --flag is not specified the "debug" flags are the',&
     '                   default. ',&
-    ' --flag  FFLAGS    selects compile arguments for the build. These are',&
-    '                   added to the profile options if --profile is specified,',&
-    '                   else these options override the defaults.',&
-    '                   Note object and .mod directory locations are always',&
-    '                   built in.',&
-    ' --compiler   COMPILER_NAME  Specify a compiler name. The default is   ', &
-    '                           "gfortran" unless set by the environment    ', &
-    '                           variable FPM_COMPILER.                      ', &
+    help_text_compiler, &
+    help_text_flag, &
     ' --list       list candidates instead of building or running them      ', &
     ' --tests      build all tests (otherwise only if needed)               ', &
     ' --show-model show the model and exit (do not build)                   ', &
     ' --help       print this help and exit                                 ', &
     ' --version    print program version information and exit               ', &
     '                                                                       ', &
+    help_text_environment, &
+    '                                                                       ', &
     'EXAMPLES                                                               ', &
     ' Sample commands:                                                      ', &
     '                                                                       ', &
@@ -1044,14 +1105,8 @@ contains
     '                   high optimization and "debug" for full debug options.',&
     '                   If --flag is not specified the "debug" flags are the',&
     '                   default. ',&
-    ' --flag  FFLAGS    selects compile arguments for the build. These are',&
-    '                   added to the profile options if --profile is specified,',&
-    '                   else these options override the defaults.',&
-    '                   Note object and .mod directory locations are always',&
-    '                   built in.',&
-    ' --compiler COMPILER_NAME  Specify a compiler name. The default is     ', &
-    '                           "gfortran" unless set by the environment    ', &
-    '                           variable FPM_COMPILER.                      ', &
+    help_text_compiler, &
+    help_text_flag, &
     ' --runner CMD  A command to prefix the program execution paths with.   ', &
     '               see "fpm help runner" for further details.              ', &
     ' --list     list candidates instead of building or running them        ', &
@@ -1059,6 +1114,8 @@ contains
     '            The same arguments are passed to all test names            ', &
     '            specified.                                                 ', &
     '                                                                       ', &
+    help_text_environment, &
+    '                                                                       ', &
     'EXAMPLES                                                               ', &
     'run tests                                                              ', &
     '                                                                       ', &
@@ -1116,11 +1173,7 @@ contains
     '                   high optimization and "debug" for full debug options.',&
     '                   If --flag is not specified the "debug" flags are the',&
     '                   default. ',&
-    ' --flag  FFLAGS    selects compile arguments for the build. These are',&
-    '                   added to the profile options if --profile is specified,',&
-    '                   else these options override the defaults.',&
-    '                   Note object and .mod directory locations are always',&
-    '                   built in.',&
+    help_text_flag, &
     ' --no-rebuild      do not rebuild project before installation', &
     ' --prefix DIR      path to installation directory (requires write access),', &
     '                   the default prefix on Unix systems is $HOME/.local', &
@@ -1132,6 +1185,8 @@ contains
     '                   (default: include)', &
     ' --verbose         print more information', &
     '', &
+    help_text_environment, &
+    '', &
     'EXAMPLES', &
     ' 1. Install release version of project:', &
     '', &
@@ -1154,4 +1209,17 @@ contains
       if (len_trim(var) == 0) deallocate(var)
     end subroutine get_char_arg
 
+
+    !> Get an environment variable for fpm, this routine ensures that every variable
+    !> used by fpm is prefixed with FPM_.
+    function get_fpm_env(env, default) result(val)
+      character(len=*), intent(in) :: env
+      character(len=*), intent(in) :: default
+      character(len=:), allocatable :: val
+
+      character(len=*), parameter :: fpm_prefix = "FPM_"
+
+      val = get_env(fpm_prefix//val, default)
+    end function get_fpm_env
+
 end module fpm_command_line
diff --git a/src/fpm_compiler.f90 b/src/fpm_compiler.f90
index c8858b7..34ac941 100644
--- a/src/fpm_compiler.f90
+++ b/src/fpm_compiler.f90
@@ -596,39 +596,62 @@ end function is_unknown
 
 
 !> Create new compiler instance
-subroutine new_compiler(self, fc)
-    !> Fortran compiler name or path
-    character(len=*), intent(in) :: fc
+subroutine new_compiler(self, fc, cc)
     !> New instance of the compiler
     type(compiler_t), intent(out) :: self
-
-    character(len=*), parameter :: cc_env = "FPM_C_COMPILER"
+    !> Fortran compiler name or path
+    character(len=*), intent(in) :: fc
+    !> C compiler name or path
+    character(len=*), intent(in) :: cc
 
     self%id = get_compiler_id(fc)
 
     self%fc = fc
-    call get_default_c_compiler(self%fc, self%cc)
-    self%cc = get_env(cc_env, self%cc)
+    if (len_trim(cc) > 0) then
+      self%cc = cc
+    else
+      call get_default_c_compiler(self%fc, self%cc)
+    end if
 end subroutine new_compiler
 
 
 !> Create new archiver instance
-subroutine new_archiver(self)
+subroutine new_archiver(self, ar)
     !> New instance of the archiver
     type(archiver_t), intent(out) :: self
+    !> User provided archiver command
+    character(len=*), intent(in) :: ar
+
     integer :: estat, os_type
 
-    os_type = get_os_type()
-    if (os_type /= OS_WINDOWS .and. os_type /= OS_UNKNOWN) then
-        self%ar = "ar -rs "
+    character(len=*), parameter :: arflags = " -rs ", libflags = " /OUT:"
+
+    if (len_trim(ar) > 0) then
+      ! Check first for ar-like commands
+      if (check_compiler(ar, "ar")) then
+        self%ar = ar//arflags
+      end if
+
+      ! Check for lib-like commands
+      if (check_compiler(ar, "lib")) then
+        self%ar = ar//libflags
+      end if
+
+      ! Fallback and assume ar-like behaviour
+      self%ar = ar//arflags
     else
+      os_type = get_os_type()
+      if (os_type /= OS_WINDOWS .and. os_type /= OS_UNKNOWN) then
+        self%ar = "ar"//arflags
+      else
         call execute_command_line("ar --version > "//get_temp_filename()//" 2>&1", &
-            & exitstat=estat)
+          & exitstat=estat)
         if (estat /= 0) then
-            self%ar = "lib /OUT:"
+          self%ar = "lib"//libflags
         else
-            self%ar = "ar -rs "
+          self%ar = "ar"//arflags
         end if
+      end if
     end if
     self%use_response_file = os_type == OS_WINDOWS
     self%echo = .true.
diff --git a/src/fpm_model.f90 b/src/fpm_model.f90
index dd79b94..38625be 100644
--- a/src/fpm_model.f90
+++ b/src/fpm_model.f90
@@ -124,6 +124,12 @@ type :: fpm_model_t
     !> Command line flags passed to fortran for compilation
     character(:), allocatable :: fortran_compile_flags
 
+    !> Command line flags passed to C for compilation
+    character(:), allocatable :: c_compile_flags
+
+    !> Command line flags passed to the linker
+    character(:), allocatable :: link_flags
+
     !> Base directory for build
     character(:), allocatable :: output_directory
 
@@ -276,6 +282,8 @@ function info_model(model) result(s)
     s = s // ', archiver=(' // debug(model%archiver) // ')'
     !    character(:), allocatable :: fortran_compile_flags
     s = s // ', fortran_compile_flags="' // model%fortran_compile_flags // '"'
+    s = s // ', c_compile_flags="' // model%c_compile_flags // '"'
+    s = s // ', link_flags="' // model%link_flags // '"'
     !    character(:), allocatable :: output_directory
     s = s // ', output_directory="' // model%output_directory // '"'
     !    type(string_t), allocatable :: link_libraries(:)
diff --git a/src/fpm_targets.f90 b/src/fpm_targets.f90
index f10b330..23f9447 100644
--- a/src/fpm_targets.f90
+++ b/src/fpm_targets.f90
@@ -483,7 +483,7 @@ subroutine resolve_target_linking(targets, model)
             if (target%target_type /= FPM_TARGET_C_OBJECT) then
                 target%compile_flags = model%fortran_compile_flags//" "//global_include_flags
             else
-                target%compile_flags = global_include_flags
+                target%compile_flags = model%c_compile_flags//" "//global_include_flags
             end if
 
             allocate(target%link_objects(0))
@@ -498,7 +498,7 @@ subroutine resolve_target_linking(targets, model)
 
                 call get_link_objects(target%link_objects,target,is_exe=.true.)
 
-                target%link_flags = string_cat(target%link_objects," ")
+                target%link_flags = model%link_flags//" "//string_cat(target%link_objects," ")
 
                 if (allocated(target%link_libraries)) then
                     if (size(target%link_libraries) > 0) then