makefile - make 总是重制 PHONY 静态规则目标

Question

我已经摸索了大约一个小时了，事实证明 Google 的用途有限。我有一个包含图表的报告的 Makefile。这些图表由 graphs/目录中的 .plot 文件表示，gnuplot 用于从它们生成 .tex 和 .eps 文件。然后使用 ps2pdf 从 .eps 生成 pdf，最后report.tex 中的 \include 命令将图形 .tex 包含到文档中，该文档再次包含图形 .pdf 以放置图形在最终报告.pdf中。

我有一个 Makefile，它可以正确构建所有内容，但由于某种原因，每次运行 make 时，make 都会坚持重新制作 report.pdf。仔细阅读 make -d 的输出发现 Make 说:“必须重新制作目标 mp-int-2.4-ni'。”和“必须重新制作目标mp-int-2.4-i”。每次运行，但这些都被声明为 PHONY，因此不应该重新制作，除非它们依赖的东西发生了变化。或者至少我是这么认为的？

对于可能导致此问题的原因以及我如何避免每次都重新制作最终的 pdf 有什么想法吗？

生成文件

GRAPHS := mp-int-2.4-ni mp-int-2.4-i

.PHONY : $(GRAPHS)
.PRECIOUS : graphs/%.pdf

report.pdf: report.tex $(GRAPHS)
    # ...

$(GRAPHS): %: graphs/%.pdf graphs/%.tex

graphs/%.pdf: graphs/%.eps
    # ...

graphs/%.tex graphs/%.eps: graphs/%.plot
    # ...

make -d 在 make 已经运行之后

$ make -d | grep -Ev "Trying|Reject|Avoid|intermediate"
Considering target file `report.pdf'.
  Considering target file `report.tex'.
   Looking for an implicit rule for `report.tex'.
   No implicit rule found for `report.tex'.
   Finished prerequisites of target file `report.tex'.
  No need to remake target `report.tex'.
  Considering target file `mp-int-2.4-i'.
   File `mp-int-2.4-i' does not exist.
    Considering target file `graphs/mp-int-2.4-i.pdf'.
     Looking for an implicit rule for `graphs/mp-int-2.4-i.pdf'.
     Found an implicit rule for `graphs/mp-int-2.4-i.pdf'.
       Considering target file `graphs/mp-int-2.4-i.plot'.
        Looking for an implicit rule for `graphs/mp-int-2.4-i.plot'.
        No implicit rule found for `graphs/mp-int-2.4-i.plot'.
        Finished prerequisites of target file `graphs/mp-int-2.4-i.plot'.
       No need to remake target `graphs/mp-int-2.4-i.plot'.
     Finished prerequisites of target file `graphs/mp-int-2.4-i.pdf'.
     Prerequisite `graphs/mp-int-2.4-i.eps' of target `graphs/mp-int-2.4-i.pdf' does not exist.
    No need to remake target `graphs/mp-int-2.4-i.pdf'.
    Considering target file `graphs/mp-int-2.4-i.tex'.
     Looking for an implicit rule for `graphs/mp-int-2.4-i.tex'.
     Found an implicit rule for `graphs/mp-int-2.4-i.tex'.
      Pruning file `graphs/mp-int-2.4-i.plot'.
      Pruning file `graphs/mp-int-2.4-i.plot'.
     Finished prerequisites of target file `graphs/mp-int-2.4-i.tex'.
     Prerequisite `graphs/mp-int-2.4-i.plot' is older than target `graphs/mp-int-2.4-i.tex'.
    No need to remake target `graphs/mp-int-2.4-i.tex'.
   Finished prerequisites of target file `mp-int-2.4-i'.
  Must remake target `mp-int-2.4-i'.
  Successfully remade target file `mp-int-2.4-i'.
  Considering target file `mp-int-2.4-ni'.
   File `mp-int-2.4-ni' does not exist.
    Considering target file `graphs/mp-int-2.4-ni.pdf'.
     Looking for an implicit rule for `graphs/mp-int-2.4-ni.pdf'.
     Found an implicit rule for `graphs/mp-int-2.4-ni.pdf'.
       Considering target file `graphs/mp-int-2.4-ni.plot'.
        Looking for an implicit rule for `graphs/mp-int-2.4-ni.plot'.
        No implicit rule found for `graphs/mp-int-2.4-ni.plot'.
        Finished prerequisites of target file `graphs/mp-int-2.4-ni.plot'.
       No need to remake target `graphs/mp-int-2.4-ni.plot'.
     Finished prerequisites of target file `graphs/mp-int-2.4-ni.pdf'.
     Prerequisite `graphs/mp-int-2.4-ni.eps' of target `graphs/mp-int-2.4-ni.pdf' does not exist.
    No need to remake target `graphs/mp-int-2.4-ni.pdf'.
    Considering target file `graphs/mp-int-2.4-ni.tex'.
     Looking for an implicit rule for `graphs/mp-int-2.4-ni.tex'.
     Found an implicit rule for `graphs/mp-int-2.4-ni.tex'.
      Pruning file `graphs/mp-int-2.4-ni.plot'.
      Pruning file `graphs/mp-int-2.4-ni.plot'.
     Finished prerequisites of target file `graphs/mp-int-2.4-ni.tex'.
     Prerequisite `graphs/mp-int-2.4-ni.plot' is older than target `graphs/mp-int-2.4-ni.tex'.
    No need to remake target `graphs/mp-int-2.4-ni.tex'.
   Finished prerequisites of target file `mp-int-2.4-ni'.
  Must remake target `mp-int-2.4-ni'.
  Successfully remade target file `mp-int-2.4-ni'.
 Finished prerequisites of target file `report.pdf'.
 Prerequisite `report.tex' is older than target `report.pdf'.
 Prerequisite `mp-int-2.4-i' of target `report.pdf' does not exist.
 Prerequisite `mp-int-2.4-ni' of target `report.pdf' does not exist.
Must remake target `report.pdf'.

在 Etan Reisner 的回答后工作 Makefile:

GRAPHS := mp-int-2.4-i mp-int-2.4-ni
GRAPHS_WD := $(addprefix graphs/,$(GRAPHS))
REAL_GRAPHS := $(addsuffix .pdf,$(GRAPHS_WD)) $(addsuffix .tex,$(GRAPH_SWD))

.PHONY : clean

report.pdf: report.tex $(REAL_GRAPHS)
    # ...

graphs/%.pdf: graphs/%.eps
    # ..

graphs/%.tex graphs/%.eps: graphs/%.plot
    # ..

Answer 1

虚假规则是您告诉 make 与实际文件不对应的规则，因此它不会检查文件是否存在，因此它始终假设该规则需要运行，因此 report.pdf 的先决条件是较新(这就是输出告诉您的内容)。

make 文档说“虚假目标不应成为真实目标文件的先决条件；如果是，则每次 make 更新该文件时都会运行其配方。” [ref]

您将这些文件标记为 PHONY 的目的是什么？