回帖：fsu0413:这样，你在你解压出来的环境里搜一下下面的正则看看输出是什么样的
’mingw-w64[\\\/]7\.3\.0‘ （不包含引号） (2021-12-12 07:37) 
不知道如何插入图片，只好贴文字了
使用findstr 命令行，查询，几乎所有的prl 文件都有D:/mingw-w64/7.3.0/
下列只能贴了部分内容
D:\ProgramFiles\Qt\Qt5.12.12-Windows-x86-MinGW7.3.0-staticFull\lib>findstr -I "mingw-w64[\\\/]7\.3\.0" *.*
libEGL.prl:QMAKE_PRL_LIBS = -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib -L$$ $$\\liblibGLESv2.a -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib -lgdi32 -lcomdlg32 -loleaut32 -limm32 -lwinmm -lws2_32 -lole32 -luuid -luser32 -ladvapi32 $$/libtranslator.a $$/libpreprocessor.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libd3d9.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libdxguid.a
libGLESv2.prl:QMAKE_PRL_LIBS = -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib -lgdi32 -lcomdlg32 -loleaut32 -limm32 -lwinmm -lws2_32 -lole32 -luuid -luser32 -ladvapi32 $$/libtranslator.a -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib $$/libpreprocessor.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libd3d9.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libdxguid.a
qmapboxgl.prl:QMAKE_PRL_LIBS = -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib $$/libQt5Network.a -ldnsapi -liphlpapi -lcrypt32 $$/libQt5Gui.a -L$$ $$/libqtlibpng.a $$/libqtharfbuzz.a $$/libQt5Sql.a $$/libQt5Core.a -lmpr -lnetapi32 -luserenv -lversion -lkernel32 -lshell32 $$/libqtpcre2.a $$/liblibEGL.a $$\\liblibGLESv2.a $$/liblibGLESv2.a -lcomdlg32 -loleaut32 -limm32 -lwinmm -lws2_32 -lole32 -luuid -ladvapi32 $$/libtranslator.a $$/libpreprocessor.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libd3d9.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libdxguid.a -lgdi32 -luser32 libssl libcrypto libadvapi32 libcrypt32 libuser32 libgdi32 libwsock32 libws2_32
Qt53DAnimation.prl:QMAKE_PRL_LIBS = -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib $$/libQt53DRender.a -L$$ $$/libQt5OpenGLExtensions.a $$/libQt53DCore.a $$/libQt5Gui.a $$/libqtlibpng.a $$/libqtharfbuzz.a $$/libQt5Network.a -ldnsapi -liphlpapi -lcrypt32 libssl libcrypto libadvapi32 libcrypt32 libuser32 libgdi32 libwsock32 libws2_32 $$/libQt5Concurrent.a $$/libQt5Core.a -lmpr -lnetapi32 -luserenv -lversion -lkernel32 -lshell32 $$/libqtpcre2.a $$/liblibEGL.a $$\\liblibGLESv2.a $$/liblibGLESv2.a -lcomdlg32 -loleaut32 -limm32 -lwinmm -lws2_32 -lole32 -luuid -ladvapi32 $$/libtranslator.a $$/libpreprocessor.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libd3d9.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libdxguid.a -lgdi32 -luser32
Qt53DCore.prl:QMAKE_PRL_LIBS = -LD:\\Jenkins7\\workspace\\Qt\\Q2wx3m7sf\\buildDir\\OpenSSL1.1.1l-Windows-x86-MinGW-GCC7.3.0\\lib $$/libQt5Gui.a -L$$ $$/libqtlibpng.a $$/libqtharfbuzz.a $$/libQt5Network.a -ldnsapi -liphlpapi -lcrypt32 libssl libcrypto libadvapi32 libcrypt32 libuser32 libgdi32 libwsock32 libws2_32 $$/libQt5Core.a -lmpr -lnetapi32 -luserenv -lversion -lkernel32 -lshell32 $$/libqtpcre2.a $$/liblibEGL.a $$\\liblibGLESv2.a $$/liblibGLESv2.a -lcomdlg32 -loleaut32 -limm32 -lwinmm -lws2_32 -lole32 -luuid -ladvapi32 $$/libtranslator.a $$/libpreprocessor.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libd3d9.a D:/mingw-w64/7.3.0/mingw32/i686-w64-mingw32/lib/libdxguid.a -lgdi32 -luser32
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下载 grepwin 查找 mingw-w64[\\\/]7\.3\.0，可看 lib文件的*.prl，lib\pkgconfig文件下的*.pc,qml文件下包括子文件夹下的*.prl都有包含的。

查看 Qt5FontDatabaseSupport.prl 的内容为：
QMAKE_PRL_BUILD_DIR = D:/Qt/build-QtQ2wx3m7sf/qtbase/src/platformsupport/fontdatabases
QMAKE_PRO_INPUT = fontdatabases.pro
QMAKE_PRL_