Delegate linker Tool.exists() to CC/CXX Tool.exists().

Even for linking, need to respect CC/CXX specified by the user (issue#1723).
And when CC is specified but not CXX, assume the user knows there is nothing
to link with CXX, and delegate to CC Tool.exists() only. However, this somehow
should be synchronized with link.smart_link() to choose the correct linker.

2 files changed, 16 insertions, 10 deletions

diff --git a/src/engine/SCons/Tool/aixlink.py b/src/engine/SCons/Tool/aixlink.py
index 35125220..4e9db21b 100644
--- a/src/engine/SCons/Tool/aixlink.py
+++ b/src/engine/SCons/Tool/aixlink.py
@@ -37,7 +37,6 @@ import os.path
 
 import SCons.Util
 
-import aixcc
 import link
 
 cplusplus = __import__('c++', globals(), locals(), [])
@@ -62,12 +61,14 @@ def generate(env):
     env['SHLIBSUFFIX']    = '.a'
 
 def exists(env):
-    path, _cc, _shcc, version = aixcc.get_xlc(env)
-    if path and _cc:
-        xlc = os.path.join(path, _cc)
-        if os.path.exists(xlc):
-            return xlc
-    return None
+    # TODO: sync with link.smart_link() to choose a linker
+    linkers = { 'CXX': ['aixc++'], 'CC': ['aixcc'] }
+    alltools = []
+    for langvar, linktools in linkers.items():
+        if langvar in env: # use CC over CXX when user specified CC but not CXX
+            return SCons.Tool.FindTool(linktools, env)
+        alltools.extend(linktools)
+    return SCons.Tool.FindTool(alltools, env)
 
 # Local Variables:
 # tab-width:4
diff --git a/src/engine/SCons/Tool/gnulink.py b/src/engine/SCons/Tool/gnulink.py
index bf71270f..3dc8f51b 100644
--- a/src/engine/SCons/Tool/gnulink.py
+++ b/src/engine/SCons/Tool/gnulink.py
@@ -37,8 +37,6 @@ import SCons.Util
 
 import link
 
-linkers = ['g++', 'gcc']
-
 def generate(env):
     """Add Builders and construction variables for gnulink to an Environment."""
     link.generate(env)
@@ -53,7 +51,14 @@ def generate(env):
     env['_RPATH'] = '${_concat(RPATHPREFIX, RPATH, RPATHSUFFIX, __env__)}'
     
 def exists(env):
-    return env.Detect(linkers)
+    # TODO: sync with link.smart_link() to choose a linker
+    linkers = { 'CXX': ['g++'], 'CC': ['gcc'] }
+    alltools = []
+    for langvar, linktools in linkers.items():
+        if langvar in env: # use CC over CXX when user specified CC but not CXX
+            return SCons.Tool.FindTool(linktools, env)
+        alltools.extend(linktools)
+    return SCons.Tool.FindTool(alltools, env) # find CXX or CC
 
 # Local Variables:
 # tab-width:4