macOS X
在 MacOS X 上，手册页对选项ld非常明确-r：
-r合并目标文件以生成另一个文件类型为 MH_OBJECT 的 mach-o 目标文件。
所以，如果你在 MacOS X 上，问题是它-lm不是 Mach-O 目标文件，也不是-lc. 但是，理论上，如果您有目标文件main.o，obj1.o并且obj2.o您这样做：
cp obj1.o ./-lm
cp obj2.o ./-lc
ld -r -o main1.o main.o -lm -lc
那么它可能会起作用。在实践中，它没有，并且在您得到的错误中：
ld: warning: unexpected dylib (/usr/lib/libm.dylib) on link line
ld: warning: unexpected dylib (/usr/lib/libc.dylib) on link line
但是，运行：
ld -r -o main1.o -arch x86_64 main.o obj1.o obj2.o
装载机没有任何抱怨的情况下工作。
Linux
On Linux the man page for ld is less explicit, but says:
-i Perform an incremental link (same as option -r).
-r
--relocatable
Generate relocatable output---i.e., generate an output file that can in turn serve as input to ld. This is often called partial linking. As a side effect, in environments that support standard Unix magic numbers, this option also sets the output file’s magic number to "OMAGIC". If this option is not specified, an absolute file is produced. When linking C++ programs, this option will not resolve references to constructors; to do that, use -Ur.
When an input file does not have the same format as the output file, partial linking is only supported if that input file does not contain any relocations. Different output formats can have further restrictions; for example some "a.out"-based formats do not support partial linking with input files in other formats at all.
This option does the same thing as -i.
Reading between the lines, this also takes object files and converts them to object files; it does not add libraries into the mix. If you think about it, object files are not created containing references to libraries.
So, although there might be platforms where it is possible to specify libraries to the linker (loader) when using the -r option, there are others where it is not.
Workarounds
The original problem is to establish whether the libraries are present. Why not mimic what autoconf does, and create a main.c that would, for preference, contain a reference to a symbol defined in the library, but which could simply contain:
int main(void){return 0;}
and compile and link it with the C compiler:
cc -o main main.c -lm -lc
If it doesn't work, then one of the libraries is missing. If you've already checked that -lc is present, then you can infer that -lm is missing.