小编Ody*_*eus的帖子

假设我有一个来自 gcc -D 选项的定义，例如

gcc -DBINDIR=\"/usr/bin\"

我想要的是在此现有定义之前添加路径，因此 BINDIR 类似于“/home/user/testbuild/usr/bin”

我试过的：

#define STRINGIZE_NX(A)         #A
#define STRINGIZE(A)            STRINGIZE_NX(A)

#define PRE_PATH                "/home/user/testbuild"
#pragma message                 "PRE_PATH: " STRINGIZE(PRE_PATH)

#ifndef BINDIR
#   error "BINDIR must be defined"
#else
#   pragma message              "BINDIR: " STRINGIZE(BINDIR)
#   define TMP                  BINDIR
#   pragma message              "TMP: " STRINGIZE(TMP)
#   undef  BINDIR
#   define BINDIR               PRE_PATH TMP
#   pragma message              "BINDIR: " STRINGIZE(BINDIR)
#   undef  TMP
#endif

在查看编译器输出时，在我看来，TMP 并未按照我预期的方式分配给 BINDIR 的值：

note: #pragma message: PRE_PATH: "/home/user/testbuild"
note: #pragma message: …