1. Do not use .c_str() to keep a persistent handle on a temporary string. 2. Concatenate -lfoo and -L/bar options into a single option instead of    passing "-L /bar" (for example) which doesn't work on Darwin. 3. Send -v output to stderr instead of stdout
1. Do not use .c_str() to keep a persistent handle on a temporary string.
2. Concatenate -lfoo and -L/bar options into a single option instead of
   passing "-L /bar" (for example) which doesn't work on Darwin.
3. Send -v output to stderr instead of stdout


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@23404 91177308-0d34-0410-b5e6-96231b3b80d8

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