linux無法編譯libevent，一直報錯，但是我有裝openssl

執(zhí)行完configure后make,報錯：

make
make  all-recursive
make[1]: Entering directory `/libevent-2.0.21-stable'
Making all in .
make[2]: Entering directory `/libevent-2.0.21-stable'
/bin/bash ./libtool --tag=CC   --mode=compile gcc -DHAVE_CONFIG_H -I.  -I./compat -I./include -I./include    -g -O2 -Wall -fno-strict-aliasing -pthread -MT bufferevent_openssl.lo -MD -MP -MF .deps/bufferevent_openssl.Tpo -c -o bufferevent_openssl.lo bufferevent_openssl.c
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -I./compat -I./include -I./include -g -O2 -Wall -fno-strict-aliasing -pthread -MT bufferevent_openssl.lo -MD -MP -MF .deps/bufferevent_openssl.Tpo -c bufferevent_openssl.c  -fPIC -DPIC -o .libs/bufferevent_openssl.o
bufferevent_openssl.c: In function 'bio_bufferevent_new':
bufferevent_openssl.c:106:3: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:107:3: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:108:3: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:109:3: error: dereferencing pointer to incomplete type
bufferevent_openssl.c: In function 'bio_bufferevent_free':
bufferevent_openssl.c:119:7: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:120:8: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:120:19: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:121:22: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:122:4: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:123:4: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:124:4: error: dereferencing pointer to incomplete type
bufferevent_openssl.c: In function 'bio_bufferevent_read':
bufferevent_openssl.c:140:8: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:143:33: error: dereferencing pointer to incomplete type
bufferevent_openssl.c: In function 'bio_bufferevent_write':
bufferevent_openssl.c:159:31: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:165:8: error: dereferencing pointer to incomplete type
bufferevent_openssl.c: In function 'bio_bufferevent_ctrl':
bufferevent_openssl.c:191:31: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:196:10: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:199:4: error: dereferencing pointer to incomplete type
bufferevent_openssl.c: At top level:
bufferevent_openssl.c:228:1: error: variable 'methods_bufferevent' has initializer but incomplete type
bufferevent_openssl.c:229:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:229:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:229:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:229:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:230:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:230:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:231:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:231:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:232:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:232:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:233:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:233:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:234:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:234:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:235:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:235:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:236:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:236:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c:237:2: warning: excess elements in struct initializer [enabled by default]
bufferevent_openssl.c:237:2: warning: (near initialization for 'methods_bufferevent') [enabled by default]
bufferevent_openssl.c: In function 'BIO_new_bufferevent':
bufferevent_openssl.c:257:8: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:258:8: error: dereferencing pointer to incomplete type
bufferevent_openssl.c:259:8: error: dereferencing pointer to incomplete type

查看106行文件，是BIO *h

static int
bio_bufferevent_new(BIO *b)
{
    b->init = 0;
    b->num = -1;
    b->ptr = NULL; /* We'll be putting the bufferevent in this field.*/
    b->flags = 0;
    return 1;
}

但是我的/usr/include/openssl目錄下執(zhí)行l(wèi)s，發(fā)現(xiàn)是存在bio.h

執(zhí)行openssl version -a：

OpenSSL 1.1.0g  2 Nov 2017
built on: reproducible build, date unspecified
platform: dist
compiler: cc -DNDEBUG -DOPENSSL_NO_DYNAMIC_ENGINE -DOPENSSLDIR="\"/usr/local/ssl\"" -DENGINESDIR="\"/usr/local/lib/engines-1.1\"" 
OPENSSLDIR: "/usr/local/ssl"
ENGINESDIR: "/usr/local/lib/engines-1.1"

目前就不知道怎么回事了
編譯環(huán)境是linux，各位給個提示，怎么查問題？

回答

編輯回答

枕邊人

這是 libevent 與 openssl 版本不兼容導(dǎo)致。

一般來說，它們的版本關(guān)系是這樣的

libevent	openssl
2.1.x	1.1
2.0.x	1.0

因此你有兩個選擇

使用 libevent 2.1.x 版本，這與你本機的 openssl 1.1 匹配，無需任何修改直接編譯即可。
使用 libevent 2.0.x 版本，你需要安裝 openssl 1.0 版本，然后在編譯時指定鏈接版本。

下面針對第二種選擇做詳細(xì)說明，這種方法是通用的，適用于編譯其他軟件時出現(xiàn)版本不兼容問題。

首先安裝 openssl 1.0 版本，注意需要頭文件。你可以選擇從源碼安裝，或使用操作系統(tǒng)的倉庫下載安裝。
這類安裝包通常帶有 "*-dev" 字樣，比如 centos 發(fā)行版可能是這樣的
```
yum install openssl-devel-1.0xxx
```
openssl 安裝完成后，會有一個 pkgconfig/ 目錄，實際路徑取決于你上一步的操作，一般位于 /usr/lib 或 /usr/local/lib 下。
這里我們假設(shè)是 /usr/local/lib/openssl-1.0/pkgconfig/，你需要將它設(shè)置成 PKG_CONFIG_PATH 的環(huán)境變量值，如
```
export PKG_CONFIG_PATH=/usr/local/lib/openssl-1.0/pkgconfig/ 
```
切換到 libevent 源碼目錄，把 openssl 頭文件路徑，及庫文件路徑加入 configure 配置變量，如
```
./configure   CFLAGS="$(pkg-config --cflags openssl)"   LDFLAGS="$(pkg-config --libs openssl)"
```
清除原內(nèi)容，并重新編譯即可
```
make clean
make -j8
```